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This might be an interesting article for those who are not interested in the Belt type "interesting" articles, i.e., the non-voodooist, non-knot-tying, non-fluoride sniffing type. Which of course won't prevent the voodooists from reading it :-).
I wonder if there is anyone naive enough to use a low powered tube amp with low to medium efficiency speakers and yet vehemently deny craving distortion? Or maybe they just don't listen to RLJ?cheers,
AJ
The threshold for disproving something is higher than the threshold for saying it, which is a recipe for the accumulation of bullshit - Softky
Follow Ups:
... and even with high-efficiency speakers where clipping is much less likely (unless they use 2 watt amps), some CD's have "clipping" built into the recording.Most people don't even know what clipping sounds like -- that might make a good thread here.
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Richard BassNut Greene
My Stereo is MUCH BETTER than Your Stereo
"... and even with high-efficiency speakers where clipping is much less likely (unless they use 2 watt amps), some CD's have "clipping" built into the recording. Most people don't even know what clipping sounds like -- that might make a good thread here."Indeed and I suspect how an amplier sounds when clipping may have more to do with why it's preferred by it's owner to other amps than does the amplifiers ability to perform on idealic waveforms.
Give me rhythm or give me death!
A pair of Klipschorns and your ears will give up long before this amplifier is even breathing hard. Especially a pair of them in the bridge-mono mode.
What's the sonic difference between an amp clipping and an amp attempting to reproduce a recorded clipped or otherwise damaged non-continuous waveform?A pair of Klipschorns and your ears will give up long before this amplifier is even breathing hard. Especially a pair of them in the bridge-mono mode.
Probably so but in no way does that mean the sound produced will be preferential to the sound of less objectively idealic performers.
Give me rhythm or give me death!
"What's the sonic difference between an amp clipping and an amp attempting to reproduce a recorded clipped or otherwise damaged non-continuous waveform?"That is a very complicated question. On the one hand we have an amplifier perfectly reproducing a distorted waveform. On the other, we have an amplifier producing its own distortion. Will it distort in exactly the same way? Who can say? Not likely though IMO. Could you hear the difference? I don't know. Probably depends on how the amplfier recovers from clipping.
"Probably so but in no way does that mean the sound produced will be preferential to the sound of less objectively idealic performers."
I look at it rather differently. I see an audio amplifier as a purely electrical device which performs a purely electrical function. If it makes a bad loudspeaker sound bad, a bad recording sound bad, it's doing its job properly. If it disguises the shortcomings of other equipment, no matter how much you may prefer to listen to that sound, IMO it is not performing its function well. IMO, the correct engineering approach is to correct the source of the distortion. In this case, chucking the Klipschorn in the trash or sending it to a museum for display would be an excellent start in the right direction.
Whether it's a 100 piece symphony orchestra, a pipe organ, or a 300 voice chorus, sound from the musicians themselves at a live performance comes from many individual directions while 90% or more of the sound comes from hundreds or even thousands of directions no one of which is predominant. This means that when the sound is 100 db at the listener's ears, the sound coming from the musicians is only 90 db, a tenth of it. Unable to reproduce that aspect of sound, all of it in a modern audio system comes from just two directions. If there is one word to characterize the sound audio systems produce when music is loud compared to the sound live musicians produce, it would be blaring. That may be "hi fi" sound but it's not high fidelity sound in my book.
["...sound from the musicians themselves at a live performance comes from many individual directions while 90% or more of the sound comes from hundreds or even thousands of directions..."]and
["...sound is 100 db at the listener's ears, the sound coming from the musicians is only 90 db, a tenth of it."]
...is your idea of reproduced sound 10% direct? If so, how do you account for 90% direct in your second assertion? Please note, the distance from the sources was omitted from both.
In my "second assertion" 10% is direct, 90% is indirect. It takes ten times as much sound power to produce 100 db as 90 db. This means that if you were to be able to block out the direct sound completely, the total sound would be imperceptably softer. Try it next time you are at a concert by placing your open hands directly in front of your ears. Most of what you will hear will be the sound that's reflected.In his famous white paper written around 1967, Dr. Amar Bose, professor of Acoustics and Electrical Engineering at MIT reported that a mere 19 feet from the performing stage at Boston Symphony Hall, he measured 11% of the sound reaching the listener came directly from the musicians, while 89% came from sound reflected off the surfaces of the hall. Furthermore, his graphs showed that the further back you went in the hall, the higher the percentage of reflected to direct sound you would hear. If there is nothing else to be gained from his paper or anything else he ever did or said, this one fact should stick in the minds of anyone interested in understanding what they hear at a live concert. He is effectively saying that the reflected sound is the big enchalada, the prize anyone who wants to drastically improve sound reproduction should go for. But after the miserable efforts of the 1970s which resulted in the quadraphonic sound fiasco, neither manufacturers nor audiophiles had much appetite for it.
Neither his speakers nor anyone else's products have been able to recreate anything like that acoustical effect. The room you hear a live concert in may have cost tens or even a hundred or more million dollars to build and more millions to tweak. It's hundreds of times larger than your listening room. Tuning it is part art, part science, part luck. To imagine that you could substitute ten times as much of the sound you have for the 90% of the sound you don't have which is so qualitatively different and still get something which sounds like a live performance even to a non critical listener is an obvious self delusion. So even if your amplifier doesn't clip, it is still not reproducing anything like what you ought to be hearing. It's not the amplifier's fault, it is a basic flaw in the limited concept of 2 channel stereophonic sound as we know it.
Boston's symphony hall is a shoebox, given the fan shape of Carnegie, how does that affect the ratio? Or for that matter, the reverberant field? To me, Bose's flaw was that he used Boston to model the rest of the world. Seems to be inept science to me :)
"But do all halls behave the same?"Not only don't any two halls behave the same, the same hall may not behave exactly the same way from one day to the next. And they don't behave the same from one seat to the next or one musician to the one sitting next to him. However, among experts in the field of acoustics, Boston Symphony Hall is considered by many of them to be the best room for listening to music in in the United States and one of the very best ones in the world. Leo Beranek certainly thought so. I commend his lecture at Georgia Tech to anyone insterested in acoustics.
"To me, Bose's flaw was that he used Boston to model the rest of the world. Seems to be inept science to me :)"
The rationale for using his research in Boston Symphony hall to justify his speaker design wasn't just bad science, it was non science. The reverberant sound field produced by the Bose 901 loudspeaker in a home listening room has virtually nothing in common with the reverberant field produced by Boston Symphony Hall or Carnegie Hall or any other concert hall in the world. How could it, a concert hall is hundreds of times larger than a home listening room. My listening room is 4000 cubic feet. My huge house including the basement, both floors, and the attic is 100,000 cubic feet. Carnegie hall is 900,000 cubic feet. How can a 4000 cu ft room sound like a 900,0000 cu ft room? I'm sure Dr. Bose would be the first to agree. Whatever rationale there is for his design (and despite the inherent shortcomings of it there were plenty of people who found its attributes overcame its drawbacks) the one he proposed in his white paper wasn't it. In short, Bose 901 cannot and does not sound like Boston Symphony Hall or any other hall. Neither do $16,000 worth of electrostatic dressing screens or anyone elses pair of hi fi loudspeakers. There is no configuration of a pair of loudspeakers or signal you can put through them which can bridge that gap.
What I don't understand from your second assertion ("...sound is 100 db at the listener's ears, the sound coming from the musicians is only 90 db, a tenth of it."), is if you start with 90dB, why would it be 10dB louder at the listener?
I think his math goes like this. Say the orchestra is playing at 105 db if measured at their location. If the sound level is 100 db at the listener position and it is 90% reflected and 10% direct then the direct sound from the orchestra must be 90db or 10% of 100 db.Very Creative!
The introduction of new equations in different locations does wonders for perspective. Very creative indeed. Thanks.
That's correct. Most of the energy comes from sound reflected off the walls, ceiling, and floors of the concert hall. The same sound produced at the same distance in an anechoic chamber would produce a sound for the listener only one tenth as loud, therefore nine tenths of the sound reaching the listener comes from the echoes which in aggregate we call reverberation. The concert hall is in effect a gigantic acoustic amplifier bombarding the listener with each sound produced again and again hundreds or even thousands of time. They can be stretched out for two seconds or more but because they come in rapid succession, they are assoicated by our brains with the original sound. They are qualitatively different because unlike the sound directly from the musicians, each echo is softer and comes from a different direction. It's spectral content constantly changes as well generally attenuating high frequencies about a third to half as quickly as middle and low frequencies. This changes the perception of the musical timbre of the instruments making them sound more mellow but because the initial sound arrives first with all of its high frequency components present, it sounds clear and has a sharp attack. By being made louder but appearing to come from a considerably further distance than would be heard in a recording played through a loudspeaker at home, the instrument appears subjectively to be much more powerful even though it is not necessarily louder. This can be best appreciated by hearing a pipe organ playing at low volume in a church or cathedral. Even though it is not loud, it is clearly a very powerful source of sound, especially at low frequencies. By contrast, a recording of a pipe organ played through a sound system at home even at very loud levels appears relatively close and feeble. It's sound is characterized by blaring rather than its sense of power. Another example is a boat's horn blasted in a harbor. It can be heard for miles around reverberating between buildings, even hillsides. It also sounds powerful even if it is far away and not so loud.
is that the hall creates the indirect effect, not the the source (speakers). The 901 design was an entertaining and successful joke.rw
I was not discussing the Bose 901 loudspeaker system. Only a fool would dismiss measurements and conclusions about concert halls from a professor of Acoustics and Electrical Engineering at MIT but that is exactly what I have come to expect from you over the years. And you never disappoint me in that regard. That the Bose 901 loudspeaker was flawed, could not produce anything resembling the kind of reverberant fields in a concert hall and that the rationale insofar as concert hall acoustics justifying its design are concern was wrong is a given fact. What does that have to do with the way concert hall acoustics work or what Bose measured in Boston Symphony Hall? But it does go a long way to explaining why that pair of dressing screens you paid $16,000 can't reproduce the sound of a live concert anymore than a pair of Bose 901s can. You are well suited to baby sit Stereo for Dummies over at Audio Review. It's more your speed when it comes to actualy knowledge. It also suits your temperment.
Only a fool would dismiss measurements and conclusions about concert halls from a professor of Acoustics and Electrical Engineering at MIT...Who said anything about dismissing the research?
That the Bose 901 loudspeaker was flawed...
D'ya think?
What does that have to do with the way concert hall acoustics work or what Bose measured in Boston Symphony Hall?
Perhaps you haven't had your Geritol this morning. The 901 was the "answer" to his research.
"Bose® Direct/Reflecting® speaker technology delivers a blend of reflected and direct sound similar to a live concert. You experience the power, impact and emotion of a concert hall performance in your own home. "
But it does go a long way to explaining why that pair of dressing screens you paid $16,000 can't reproduce the sound of a live concert anymore than a pair of Bose 901s can.
Drawing conclusions on things completely outside your experience is one of your enduring qualities, SM. Speculate as you will. :)
BTW, your other guess as to the price is likewise incorrect.
rw
Are you just jealous of someone in particular who built a billion dollar a year privately owned business from scratch because you can't or do you have a general disdain for anyone who actually has any real technical knowledge because you don't?
By all means, do return to your pontifications. Why did you bother to respond?Are you just jealous of someone in particular who built a billion dollar a year privately owned business from scratch because you can't or do you have a general disdain for anyone who actually has any real technical knowledge because you don't?
Neither. I am amused, however, by those engineers who draw simplistic and incorrect conclusions using their "technical knowledge". Your faith in the relevance of THD is another example. In Amar's case, such resulted in one of the most fortuitous cases of dumb luck ever. Technical knowledge had nothing to do with it. More power to anyone who can become successful - by completely missing the point! They have, however, raised the bar for anyone studying marketing.
rw
So you also have disdain for engineers. All engineers or just electrical engineers?
a software engineer. While I now work in a sales role communicating the value proposition of applied technology, for years I wrote sophisticated inventory management code. I am inherently a techie geek.I learned long ago, however, that it is the considered application of knowledge that is of value, not blind acceptance. Most electrical engineering (like IT) is cut and dry. When you flip the switch, the light works or it doesn't. The program accurately calculates the double exponential smoothed usage trend or it doesn't.
The particular application to audio is fundamentally different. Even you acknowledge the limitations of the metrics on which many engineers place too much emphasis. They focus on the trees and completely miss the forest. The qualitative component to audio reproduction eludes quite a few otherwise talented engineers. Fortunately, there are quite a few who really get it. It is they who advance the art, not the junior varsity team at Crown who worship at the alter of THD. Specs look great therefore it must be good, right? Wrong!
We have some exceptionally smart guys on our development teams who really have no idea whatsoever as to the end user's specific needs or how these customers interact with the software they write. They just burn out the code. And sometimes make some really dumb user interface mistakes. Similarly, there are quite a few audio engineers who just burn out designs with no notion of how well they actually perform in the real world.
rw
I thought you were a computer programmerBTW, what is a software engineer? When I went to school, there was no such thing, just people who wrote computer programs. Did you have to take regular engineering courses like Calculus, Differential equations, physics, chemistry, material science, thermo, fluid dynamics etc.? I've tried my hand at programming PLCs...PID loops etc. but I don't think that's software engineering. So what is it?
SEs do more research and design work.BTW, what is a software engineer?
A google search yields slightly over 71 million references. Here's a simple definition:
We even have our own institute at Carnegie Mellon: SEI
When I went to school, there was no such thing
The field of IT has changed a wee bit since '62. :) Fortunately, I missed the whole punched card thing.
Did you have to take regular engineering courses like Calculus, Differential equations, physics, chemistry...
The first three, yes. Logic. Low and high level language theory. You won't find Chem in most IT curricula.
rw
E-Stat - The first three, yes. Logic.And obviously didn't learn a damn thing LOL.
BTW, I got a great laugh at your "system" info. It looks more like the result of a witchcraft convention than any sort of engineering discipline. Plenty of crutches to prop up the feeble mind.
"Harmonic Technology Magic power cords". Indeed.
"Various JPS Labs Superconductor cables". At room temperature huh? Oh yes, I forgot you "took" physics but skipped chemistry.
"Hospital grade outlets". Mental, I imagine?Cheers (Laughing as I type)
AJ
p.s. Decent speakers though.
The threshold for disproving something is higher than the threshold for saying it, which is a recipe for the accumulation of bullshit - Softky
Real engineers provide information to help people better-understand the subject matter at hand. The phonies are the ones who ridicule and "laugh at" whoever they deem unworthy of technical discussion.I've often heard more-sane technical comments on audio from some who couldn't recognize a quadratic equation than from some who trumpet their experiences with partial differential equations....
There are too many self-proclaimed "experts" out there who instead of kindly explaining the subject matter, try to disqualify people from technical conversation because of "lesser credentials." It's pathetic.
Considering your treatment of JJ and your near total lack of any resemblance of respect for the engineering profession, including the disparagement of know facts and research, I can only come to one conclusion: You are nothing but a troll.
Now tell us Todd: how's your research into fuse directionality these days? Is it north to south or east to west?
d.b.
..but I play one on TV (Never claimed to be one either).
Plus I started staying at Holiday Inns after JNeutron admitted that he did too.
One doesn't have to be an engineer to believe in science, to be objective rather than subjective. It certainly helps to have had a core education based on science, rather than say, the occult.
Makes the marketing claims of the Charlatans and hearing effects of the Audiophool all the more amusing.
Can you tell me one single solitary subjectivist here who is suddenly going to snap out of it and become objectivist just because of some engineering lessons? Tom Servo or JNeutron cause anyone here to awaken lately? The subjectivist isn't here to learn science. The subjectivist is here to learn how to try to twist science to fit their belief, learn how to try to cast a shadow of doubt, like the Intellegent Designists. Or maybe just sell some products.
What am I supposed to do, cry and rant like ol TB54? There is far too much amusement here for me to do that. Teach? To who?
For hysteria or a descent into sheer madness I could go to the cable/tweaks asylum, but there seem to be enough escapees here to provide a decent show.cheers,
AJ
The threshold for disproving something is higher than the threshold for saying it, which is a recipe for the accumulation of bullshit - Softky
Seems to me AJ that you just cannot get me out of your mind! Even when I make every attempt to talk about the subject at hand and not about the people and their particular preferences you want to bring me into it your childish games by refering to my posts as only crying & ranting!The reality is YOU are acting like a troll! This post is a perfect example wherein you're attempting to provoke me into another round of arguing with you, as you never debate, so you can once again ignore my questions and claim I'm only crying & ranting? Anyone who reads any of your posts can plainly see you are the childish one here. Your ONLY response to anyone who disagrees with your POV is to just call them as another one of those voodooist, not-tying, fluoride sniffing type of music lover who's trying to twist science to fit their belief or attempting learn how to try to cast a shadow of doubt.
I've noticed over and over that you're uncapable of defending your POV in an intelligent manner. So you are 100% correct you cannot teach anyone here. How could you when your mode of operating is strictly berating those who disagree with you and then criticizing their choices in audio components? AJinFLA in order to teach anyone, you'd need to posess the ability to discuss your POV intelligently with those who question your POV and may disagree with it. That unfortunately is not something I've seen you do as of yet.
As far as crying & ranting, this is something you do in almost every post you make. You cry about how the Objectivist way is the one true way and rant that Subjectivists are voodooist, not-tying, fluoride sniffing types who are constanly trying to twist science to fit their beliefs. It's case of the pot calling kettle black AJ.
I'll keep waiting to see if you can teach YOURSELF to act like an intelligent adult who actually discusses the topic at hand rather than a childish little troll who'd rather only talk about those who disagrees with his POV. Should that be the case and you actually do want to intelligently discuss a topic you raised (which I doubt) I'll allow you to try addressing the questions I originally posed, that is "If" you honestly believe what you stated: "I wonder if there is anyone naive enough to use a low powered tube amp with low to medium efficiency speakers and yet vehemently deny craving distortion?" and weren't simply intending to berate those who use powered tube amp with low to medium efficiency speakers, because it's a differeing technology than what you prefer? So giving you the benefit of the doubt and assuming you honestly believe your question is a valid one, I'll ask once again AJinFLA can you prove 1) The distortion is audible, 2) It's heard and noticably recognized as distortion & 3) One must be naive to believe differently than your POV?
Ok your turn, have anything intelligent to say? Or are you going to cry and rant some more?
Thetubeguy1954
"Real engineers provide information to help people better-understand the subject matter at hand."Not necessarily. Engineers are not educators, they are problem solvers. Now when it comes to providing information, telephone operators at directory assistance do that too. That doesn't make them any more qualified to design amplifiers than an audiophile wannabe electronics design engineer.
"The phonies are the ones who ridicule and "laugh at" whoever they deem unworthy of technical discussion."
Apparantly pointing out other people's technical blunders is not in the scope of an engineer's permitted activities, especially if his words are sometimes less than kind. Engineers are not allowed to get exasperated at repeated stupidities. Being walking calculators they are not subject to human emotions and reactions and such display is unacceptable from them.
"I've often heard more-sane technical comments on audio from some who couldn't recognize a quadratic equation than from some who trumpet their experiences with partial differential equations...."
A rock in a steel oil drum tumbling down a hill may make a lot of noise but that's all it makes. It's hardly surprising when another rock thinks that noise is music. If you can't solve differential equations, you cannot become an electronics design engineer. You may become a technician or a tinkerer and even produce something useful now and again but that is not the same thing as being an engineer. Engineers don't guess. Engineering doesn't rely on theorizing, that and the testing of theories are the province of scientists. Engineers apply proven scientific principles to solve well defined problems and the efficacy of their solutions can be tested objectively and evaluated in terms of how well they met their stated goals. The rest is voodoo. If people who are engineers engage in experimentation based on wild unproven hunches, then at that moment they are not performing engineering, they are tinkering. Engineers when they are engineering don't guess.
"There are too many self-proclaimed "experts" out there...."
Yes there are, and engineers here call those people for want of a better word "subjectivists" or....snake oil salesmen.
"...try to disqualify people from technical conversation because of "lesser credentials.""
Technical conversations of necessity involve technical issues which engineers can become knowledgeable about because of their very rigorous training. While engineers normally don't ridicule those who were trained in other lines of work because they didn't have the opportunity, the interest, or quite frankly the capacity to become engineers, they can't take their bogus theories and fantasies seriously either. And that is stil true even if those bogus ideas are expressed by other trained people who should know better because of their own technical education. BTW, just because someone is trained in one area of engineering, that doesn't make him qualified as an expert or even particularly knowledgeable in another. A civil engineer is no more qualified to design and electronic circuit than an electrical engineer is to design the foundation and steel superstructure of a building. As for software engineers, other than writing computer programs, I have no idea what they are qualified for professionally (and I'm not even certain they should be considered engineers. That's something I'll have to think about.) This notion of interchangeability, adaptability, or universal technical knowledge is a common mistake among managers who assign technical experts in one field to take charge of a project or oversee a department whose work in another they know little or nothing about. The results are often a disaster and the people who actually do the work become demoralized and quit.
Engineering (real engineering, not other professions with the word engineer tacked on to it) and the physical sciences are among the most difficult, rigorous, and demanding fields of endeavor to train for and practice. Unlike many other professions such as law, medicine, history, or education, the memorizing of lots of facts after reading endless voluminous tomes and attending countless lectures is not the goal of a such an education. The facts can always be looked up in a book. Engineers and scientists are taught HOW to think, not WHAT to think. And therein lies the big difference. This forum was created to focus on technical discussions. There are other forums here more suitable for mental masturbation such as Cable Asylum.
If the likes of you were in the presence of Thomas Edison, he never would have become the brilliant inventor that he was..... For based on your criteria, he'd have no business even discussing electrical concepts, let alone experimenting with them.By the way, I do have an EE degree. I'm currently a software engineer. I don't bring it up because in a technical forum, I think it really isn't necessary. Explaining the concepts alone should suffice.
Another E-stat, surprise, surprise.It's one thing to get a degree in engineering, that's an entry ticket. It's quite another to BE an enginineer. That generally takes at least 5 years of actual work in the field. It took me longer. I'm still thinking about whether or not software engineering is really engineering or whether it's just high level computer programming with the word engineering tacked on to glorify it.
BTW, I extend the same offer I made to Jon Risch. Tell me the name of the school you attended and graduated from and I'll petition them for a full refund of your tuition money. IMO, they didn't earn it.
"It's one thing to get a degree in engineering, that's an entry ticket. It's quite another to BE an enginineer."This is why trumpeting credentials (and demeaning others' credentials) serves no purpose other than self-aggrandizement. And "being" an engineer can take on numerous forms. From designing a superior product to helping those not up on the subject matter get some understanding of it.
"Tell me the name of the school you attended and graduated from and I'll petition them for a full refund of your tuition money. IMO, they didn't earn it."
Don't worry about the refund. I would have sought it myself if I thought it was a waste of time and money. I got my degree in 1985 at Case Western Reserve University.
Half the problem is because I am very familiar with a lot of what's discussed here, I find it galling whenever someone does post questionable information here, they first think nobody else is knowledgeable enough to notice anything questionable. And then use their credentials to overrule any challenges to the information. Some examples of this is the notion that applying "dither" is useful in D/A conversion (it isn't), higher oversample rates in D/A conversion improve S/N ratio (they don't necessarily do so), upsampling and oversampling improve resolution (they don't), and that the "sinc" function in digital filters is applied in the frequency domain (it's applied in the time domain). I'll try to kindly correct such information and explain why, but then Hell breaks loose. Be it accusing me of posting "misinformation", accusing me of not knowing the subject matter, or introducing irrelevant facts that convolute the issue.
If you do a search on AA, the worst thing I've done here was call some people "phonies." And levied the general accusation that some people post engineering facts but are unable to explain why. I've never used credentials as an overruling tool. I've never sought validation or consensus as an overruling tool (I call this "tag team"). I've never called anyone "charlatans" or "luddites". I've never demanded apologies. I've never questioned someone for purchasing products that may be of corrupt design and costs a lot of money. I've never accused anyone here of posting incorrect information. I just kindly correct it. I've never accused anyone of not knowing the subject matter. I've never accused anyone of lacking technical knowledge or background. And I've never told anyone he or she has no business engaging in technical discussion. I think it's totally unnecessarily to denigrate someone simply because he posts something that's questionable. Or denigrate someone who seems to lack familiarity with technical matters. I actually **enjoy** explaining things in plain speak, and do so to my best ability.
Hence I'll be willing to take arrows from the people here. For the information itself is what's important here, not the person who provides it.
And if I'm wrong, and am kindly corrected, no problem either. And I've been wrong and corrected **lots** of times. Nobody's perfect here.
And here I always thought Case Western was a pretty good school.I think I might just restrict my discussions to anyone who is not a software engineer....or a physicist.
I've heard more sense about computers from guys who didn't get out of the fourth grade and couldn't solve a quadratic equation than from some so called software engineers. How do you like the sound of that? How about.... you're in computers, my 3 year old grandaughter knows how to program a computer too. She's a real whiz at it. Why is it that every time you open your mouth....
My offer still stands.
"I've heard more sense about computers from guys who didn't get out of the fourth grade and couldn't solve a quadratic equation than from some so called software engineers."I've stated this numerous times about engineers in general..... Being an engineer isn't sacred. Nor does it imply that what he or she says should be taken as unquestionable truth.
Case Western Reserve *was* a good school, but I think its reputation has diminished in recent time. The school was once renowned for its biomedical engineering program, but I'm not sure if it was sustained. My biggest complaint about that school was I thought it had a lot of "dead wood" amongst its researchers and professors. I had a electromagnetics professor there who was an expert of stretching five minutes of material in a one-hour time slot. It was embarrassing.
The school I went to, Stevens Institute of Technology had some of the best professors anywhere and unlike more prestigious schools, you could get any and all of them as an undergraduate. Graduate assistants were NEVER substituted for the real thing. These guys sometimes floated around between teaching at Stevens, Brooklyn Poly, and other high prestige schools in the area. Some also did consulting work on the outside as well as research. Many of the very textbooks we used were written by them (what a way to sell more of their own books.) It was an outstanding school to receive an engineering or science education as an undergrad in. The same quantum chemistry text I used as a freshman was being used by a neighbor of mine in a Junior honors level course at Columbia University. There was no "dead wood."Having thought about "software engineernig" I have come to the tentative conclusion that it is not an engineering course in the traditional sense. Engineering is science applied to problem solving. Some engineering schools may offer software engineering programs but apparantly there are others which don't because they are not necessary to that field. Engineers must therefore learn basic science including physics, chemistry, material science, mechanics (statics and dynamics) thermodynamics, fluidics among others, and mathematics including calculus, analytic geometry, differential equations, statistics and probability, and then their many specialized courses in their major field of study. Software engineering seems to me to be a completely separate branch of study inclusive of itself in the same way pure mathematics is but it is not mathematics either in the ordinary sense. Software is a tool engineers can and sometimes must use just as math is but it is not a traditional engineering course. While at the better schools, a software engineering course of study could be enhanced with some traditional engineering courses it would seem they don't have to be and often aren't. BTW, industrial engineering (the stopwatch guys) also isn't real engineering. I had a boss once who was one and he'd be the first one to tell you so.
Solving customer's application problems, solving usability problems, solving efficiency of resource problems, solving code extensibility problems, solving operating system compatibility problems, etc.Engineering is science applied to problem solving.
Per cisely, SM!
You cannot design an application without understanding the problems you are trying to solve. In many cases, the solution involves not just the end product of coding a suite of programs to achieve a certain goal, but the reengineering of an entire business process. That requires an initial and thorough analysis of the many facets of the problem. The application of warehouse management systems is a great example of a completely different approach to a common set of problem.s The result significantly changed the way in which material handlers process orders completely exclusive of the way in which they interact with the various SW/HW components.
rw
Todd, not to disagree with you on this point, but I think that we should clarify one subject. When we take college courses, there are generally prerequisites that are required before one can take the class. Why? Well, because it is almost impossible to effectively teach people who are not up to the technical level of the class, because they do not have the background for it. It is the same with technical discussions here (once in a while).
Of course, if one is a really good teacher and well understands the material, then a larger audience can be taught, but I for one, would not want to try to teach partial differential equations to someone who had not taken calculus.
How about deriving the fundamental differential equation for a direct radiator loudspeaker as shown by Rice and Kellog in 1925 when they invented it? Anyone for dot notation?
"Todd, not to disagree with you on this point, but I think that we should clarify one subject. When we take college courses, there are generally prerequisites that are required before one can take the class. Why? Well, because it is almost impossible to effectively teach people who are not up to the technical level of the class, because they do not have the background for it. It is the same with technical discussions here (once in a while)."I could not disagree more. The purpose of the prerequisites in college courses are to make sure the available openings to take the course are filled with people who are least-likely to waste those spaces in the form of flunked results or diminished expectations. It is also to prevent a possible slowdown in the teaching of the material because time is limited within the quarter or semester.
In the case of this forum and others like it, there is no time constraint or limitation of space. If one doesn't know the material but wants to learn, we just need to be patient and keep a smile. Do whatever it takes. The more people learn, the better decisions they make in choosing audio components.
I cannot speak for others, but I personally get as much appreciative feedback from technical explanations as I do component or music recommendations. For it often translates into better decisions for those acquiring audio equipment.
"Of course, if one is a really good teacher and well understands the material, then a larger audience can be taught, but I for one, would not want to try to teach partial differential equations to someone who had not taken calculus."
I'd teach the calculus first.... He might then realize he may not be interested in going further into diff eqs.
"How about deriving the fundamental differential equation for a direct radiator loudspeaker as shown by Rice and Kellog in 1925 when they invented it? Anyone for dot notation?"I'll pass. I really think deriving technical equations does not accomplish a thing (aside from exhibiting mathematical skills) if the concept behind the derivation is not understood. I once took a physics course where such frivolity was a primary requisite for course passage, and I thought it was a big turn-off. For after I finished the course, I thought I didn't learn anything qualitatively about the science.
Todd, I'm sorry, but I think that understanding the equations is important to more deeply understand the component. I thought that was what I went to college for. I don't teach high school, because I don't have to patience to teach you or anyone else the basics that you should have learned on your own. Learn them first, and then we can talk.For everyone else, the reason that I mentioned the differential equation describing the direct radiator loudspeaker, was because it is a classic differential equation that can give real insights as to why a Manger speaker is different from a classic direct radiator, and how horn loading can change the cone motion of a loudspeaker. I find this interesting and important, but it also separates the 'men from the boys' in this discussion.
"Todd, I'm sorry, but I think that understanding the equations is important to more deeply understand the component. I thought that was what I went to college for."I went to college to learn how the applicable sciences work. The best professors IMO describe qualitatively what's going on, and only then do they use equations to supplement the discussion, and how to calculate the applicable parameters that are part of the material.
Take for instance the voltage-current equation for an inductor.... v = L di/dt. (The "di/dt" represents the instantaneous change of current with respect to time.) It's a simple equation, but if one who doesn't have a grasp of what voltage and current do physically speaking, he'd have to memorize the equation to solve the problems associated with the course material. It's in such case nothing more than a math exercise. But I remember the equation because of the nature of how potentials and current interact in an inductor. Voltage only appears across it whenver the current is changing. One can describe this in further detail regarding why this occurs. The electromagnetic nuts and bolts. The equation then becomes a lot more meaningful.
Someone in high school recently made a "shocker" device with a flashlight battery, switch, and transformer. He wondered why the biggest "shock" occurred when he opened (not closed) the switch. If I initially told him V = L di/dt, he wouldn't have a clue what I was talking about. I told him that voltage occurs across the inductor whenever the current changes. When the switch is engaged, the battery side of the transformer sees less impedance than when it's released. So a far greater voltage spike occurs when the switch is released. Hence the biggest "shock" occurs at the release of the switch.
Now if I tell him V = L di/dt (provided he's familiar with calculus), he'd be able to tie the math to the science.
"I don't teach high school, because I don't have to patience to teach you or anyone else the basics that you should have learned on your own. Learn them first, and then we can talk."
Don't worry, I've learned it. But not everybody here has, and I say it's arrogant to project an attitude that people who haven't learned what they could is reason to shut them out of technical discussion. (I don't remember you ever being this way in the past, John.)
If someone isn't willing to explain something technically to an average Joe here, I'd be happy to take up the slack. If it results in greater satifaction with what he does with his audio system, it's definitely worth it.
Too much "I know it and you don't" attitude, not enough "This is how it works".
Todd, I actually think that you and I are in general agreement. IF I can find a way to explain something without math, I will willingly do so. Sometimes the math is important, however, and it actually makes it easier to more fundamentally understand the actual process involved. That's what separates 'engineers' from 'techs'. I've been both.
"If someone isn't willing to explain something technically to an average Joe here, I'd be happy to take up the slack"Yes but who is going to explain it to you first?
This isn't a training school for dummies. That's over at Audio Review. E-Stat can direct you, he's a babysitter there. When you have the knowledge of an eight year old, they only ones you can lord it over are five year olds.
"Yes but who is going to explain it to you first?"Maybe you should do so.... [-;
This isn't a training school for dummies.Despite your revered presence. AA gets the same kind of basic questions. Like, for example:
At the expense of confusing the issue with facts, you posted at AR long before I did.
rw
"At the expense of confusing the issue with facts, you posted at AR long before I did."Yes but I left when the new management took over and decided that any question more complex than which HT receiver should I buy at Costco this week was too much for their site. You on the other hand got a job with the gestapo. Vee haf vays.
you just didn't like posting on the AR equivalent to Prop Head called the Audio Lab. Naturally, that makes no sense at all given your propensity to post here.rw
I figured that you would not respond. Most of you 'engineers' don't even know what I am referring to, do you?
musically and equipment wise? You have the advantage here as to comparing notes.And you seem to have gotten SM all hot and bothered, too. :)
rw
Find all that voodoo rubbish in your system indefensible huh?
Rather attack mine to distract from yours?
I'll oblige Mr 78rpm fidelity:
http://www.audioasylum.com/forums/prophead/messages/22344.html
Too vague for those who listen with their eyes? Ok:
SCD-CE775> DEQ2496> DCX2496> AVR330 8ch volume> Internal amp 55W (/ch)> Tweeter, Audiosource 200W> Mid, QSC 3500 450W> Woofer, Rythmik Servo 370W> Subwoofer.
XT19 w/ Waveguide, W22, XLS12, DS12.
Radio Shack wires and cables. Stageworks 8 outlet power center. Whatever power cords that came with equipment. Several miles of copper wire from power station to neighborhood > house > attic > walls > Home Depot UL outlets. Vacuum tube TV. Defluorinated plants in living room. Magic wand in 2nd bedroom closet left over from Halloween.Oh yeah, the entire speaker system is being revised into a 6-way, with a FBQ2496, Rane XO and 2.1kw Digital Sub amp(s) added. Might even try some CAT-5 to wire the new rig like Tom Servo suggests cuz I can get a roll for free.
Fire away sound from vision :-).cheers,
AJ
The threshold for disproving something is higher than the threshold for saying it, which is a recipe for the accumulation of bullshit - Softky
Although I've never heard the Orions, I have only heard good things about them. I've always preferred baffle-less speakers ever since I sold Dahlquists back in the 70s. That reminds me of another designer who favors such, Carl Marchisotto. He's a really nice guy. Ever heard these?:They are capable of creating a most convincing soundstage.
Find all that voodoo rubbish in your system indefensible huh?
Marketing folks do get kind of carried away with product names, don't they? The Harmonic Tech power cords are 8 gauge using 6N silver with multiple RFI shields. They work quite effectively with my ten amp draw monoblock amps to minimize all noise found in the AC. I'm surprised you didn't pick up on their color, since I find the purple a bit gaudy. Then again, I didn't buy them based on cosmetics. JPS Superconductors are merely very well shielded low capacitance cables. Like the Magics, the shielding is so stiff, they will hold any shape. The Leviton outlets are required due to their higher contact resistance than your basic $.95 outlet. The Magics had trouble pulling themselves out of the wall. :)
Rather attack mine to distract from yours?
Why would I "attack" your system? You mistake me for someone far younger or insecure. It appears you may be a speaker builder since you name each of the drivers used in your Orions and have pics on your website. I never developed that much enthusiasm for the nuts and bolts of the gear. As for the H-K Receiver, I suspect it is quite similar to my NAD T763 in resolution. I know its performance envelope quite well. I had an H-K Citation 11 preamp back in '74. Nice unit. Speaking of names, does that mean the designer got eleven speeding tickets during its development?
The only criticism I might voice has to do with the room itself. You have quite a challenge with all of the hard and reflective surfaces. Cinder block walls behind the speakers, shiny hardwood floors, floor reaching glass to the left covered only by plastic? shutters, and glass block to the right under the spiral staircase. Is that a black chaulkboard above the cinder block? Seems to me you would have a rather nasty slap echo issue. I'm not sure if you may have a WAF issue, but in my college days, I hung large tapestries on the back wall to tame the reflections and always had carpet on the floor.
Several miles of copper wire from power station to neighborhood
Ever use a water filter before? Power conditioning strategies are not intended to fix problems with the local sub station. There is nothing to fix. The problem(s) exist within your house, some of which are inches away from the amplifiers. Ever heard of RFI? Perhaps you do not perceive that to be an issue in your house. As a computer guy, I have four computers, a router, two wireless access points, four wireless phones, three digital cable boxes and six CD/DVD players that all happily spew RFI back into the AC and to the nearby area. If you don't believe me, tune an AM radio off station in the vacinity of a CD /DVD player. Hear the garbage whose IM products are only too happily amplified by your wide band amplfiers.
Thanks for the detailed reply, but you didn't answer my first question. What kind of music do you enjoy?
rw
The black felt covers 2" of acoustic absorber. When listening, the speakers were out 4' into room. The ceiling is 22'. Rug not in picture.
I heard an Alon several years back. Nice, but I need dipole bass to at least 50hz or so. Then I let the pressure source take over.
The Soundlabs and large Apogee's that I have heard would probably satisfy 90% of my audio needs. My own preference is for the sheer power of dynamic drivers, although ribbons also have their allure.
The HK's function is purely 8ch volume control and tweeter amp.
I had a Sunfire Theater Grand in there and could hear no difference.
If there is a component out there that would yield higher resolution or even just an audible difference, it would be in the 1-2% range.
In other words, *very* subtle difference, if any. Simply not worth my time pursuing when the HK does its job for very little $ and my time/effort can then be concentrated on improving my speaker system, the room and the speaker/room interface, which makes up 95-98% of the difference in every audio system I have ever heard.
I choose to spend my finite resources on what I find to be most important to the sound.
Music? I like it all. Acoustic Jazz, electronic Jazz, Latin Jazz, Classical, Big Band, Light Rock, Hard Rock, Metal, Pop, Dance, Blues, Folk, Country, Reggae, etc, etc. Not just lip service or to appear cool. I actually have tons of cds in all those genre's. I was an early adopter of XM. Not for the SQ! Mainly because of the variety. I'm listening to it right now. Perfect for when I surf. OB Tannoy ICT driver DIY computer speakers of course.
I try to attend as many concerts as possible to remind myself of how far away I really am each time I listen to something recorded. I use to go to the high end stores as often as I could for reality checks when designing my speakers. I dont hardly anymore since I haven't heard anything recent that I would trade my system for (yes, I'm well aware of Beraneks law LOL). It was designed by me and optimized for my specific room and tastes (neutrality and realism as I know it). Thats tough for a designer sitting somewhere else trying to please the masses to compete against. I haven't seen too many DSP driven, room adaptable OB (or electrostat/ribbon/boxless) in showrooms. Looks like there was only 1 at RMAF. I suspect we will see more as time marches on.
As long as those fancy cables don't degrade the sound, I see nothing in your system that I would object to sonically other than maybe the records, which I'm not too fond of. The speakers are not boxes, the amps are tube, but have plenty power, you have a CD player, so yeah, I'd most likely be just fine with the sound.
BTW, as I noted previously, I have a different listening room now and so the speakers are being revised to reflect higher SPL capabilty - due to lower neighbor proximity.
I'll post it here when I'm done and give my impression of Tom Servos demo - and its effect on the neighborhood.cheers,
AJ
The threshold for disproving something is higher than the threshold for saying it, which is a recipe for the accumulation of bullshit - Softky
Maybe I should adopt John Curl's position of a couple of years back when he wouldn't respond to postings by anyone who wasn't a degreed electrical engineer. Well, that would let him out. And E-stat. It still looks to me like a so called "software engineer" is a glorified computer programmer especially since you can learn it at a two year community college. Today everyone is an "engineer." A janitor is a "stationary engineer" a trash collector is a "sanitary engineer" so why not call a programmer a "software engineer." Yestidee I couldn't spell Inganeeeer, today I ARE one.
Is that true? Interesting, he talks to me despite my total lack of any formal engineering or electronics training.John must have mellowed with time.
He found that he had almost nobody to talk to. So probably out of loneliness as much as out of ego, he finally condescended come down off Mount Olympus and to speak to mere mortals."So this is good old Boston.
The home of the bean and the cod.
Where the Lowells talk only to the Cabots.
And the Cabots talk only to God.""I dwell 'neath the shades of Harvard
In the State of the Sacred Cod,
Where the Lowells speak only to Cabots
And the Cabots speak only to God"
http://www.whonamedit.com/doctor.cfm/1906.html
Soundmind, where do you get these ideas? Also, why do you always bring me up for discussion? I don't know you, and you don't know me.
"I don't know you, and you don't know me."Let's keep it that way. How nice that there is an entire continent between us. And to think 25 years ago when I lived in the Bay area, I might have run into you.....but I wouldn't have known you from a bag of sour apples.
"why do you always bring me up for discussion"
This particular time it's because I am contemplating adopting your once strict policy of not responding to those who do not meet certain qualifications. On reflection, I've decided there may have been merit in that idea after all and I was hasty dismissing it out of hand. Among those I may not respond to in the future are so called "software engineers." Maybe physicists too. I haven't decided yet.
Soundmind, I can't recall that you have ever said anything useful about audio reproduction. You 'might' know something about classical instruments, but you are clueless when it comes to audio electronics. I doubt that you really understand how anything is designed, especially at an engineering level. We really don't need your 'input' here to us, so why don't you do what you say you are going to do, and leave us out of your rants? Power engineering is not electronic engineering, folks.
"Soundmind, I can't recall that you have ever said anything useful about audio reproduction"Likewise!
"Power engineering is not electronic engineering, folks."
Neither is tinkering to build a circuit whose ultimate criteria is that it sounds good...to someone who is likely half deaf from self inflicted injury.
LOL
The threshold for disproving something is higher than the threshold for saying it, which is a recipe for the accumulation of bullshit - Softky
.
I would imagine you've given E-Stat a few laughs as well with your "fit for a roller rink PA system" pro gear. I'm sure it does well with disco music and "Roll Out The Barrel" for when it's Geriatric Night down at the ol' skating rink. LOL!Gosh, you're right - it IS fun to laugh at the other side. :)
Kerr - "fit for a roller rink PA system"You mean the stuff used to make most all your recordings? All your recordings sound like roller rink PA's? Thats most likely due to all the props holding up your feeble mind, littering your system.
Kerr, do you remember anything from Calculus, Physics, Chemistry or Diff EQ? No? Not too much science after Kindergarden huh?
Hey as David Hannum said: "There is a sucker born every minute"
And every 10 minutes, there is someone born who will sell something to that sucker.
See Kerr, the charlatans can't exist without you. The pied pipers need rats just like you. Their willing subjects. Enjoy the tune!cheers,
AJ
The threshold for disproving something is higher than the threshold for saying it, which is a recipe for the accumulation of bullshit - Softky
Ever take any music classes? It's kinda like that "Stayin' Alive" tune that comes out of your PA system but it's different - a little more involved... beyond your grasp apparently. Hmmm... don't know what live music sounds like, eh? Not too surprising. While you were studying physics and chemistry and learning about the metrics for sound systems, you missed the part about practicability. It's supposed to sound like MUSIC, not static. David Hannum was taking about YOU, sport! LOL! But hey, your crap system is accurate, right? LMAO! Sure, if you're into disco! Go back and measure... listening to music isn't for you. Music is all mathematics anyway. And besides, all those people making truly high definition audio components are all rolling in dough, thanks to "voodoo-ists" like me.Enjoy your PA. All this stuff sounds the same anyway. Ah well, better stop before I get thrown outta here. It was fun, though. The last word is yours, Tony Manero.
Kerr - Ever take any music classes?Not in college that I can recall. Would have been an elective.
Kerr - It's kinda like that "Stayin' Alive" tune that comes out of your PA system but it's different
I'll take your word for it.
Kerr - beyond your grasp apparently. Hmmm... don't know what live music sounds like, eh? Not too surprising.
Made no sense, but I'm sure it did to you.
Kerr - While you were studying physics and chemistry and learning about the metrics for sound systems, you missed the part about practicability.
I did? Was this in the music classes you were taking? You mean a practicable way to buy mega-expensive wire? Wooden knobs? Brass feet? March behind the pied piper? Yeah, I guess I missed all that. Shame.
Kerr - It's supposed to sound like MUSIC, not static.
Right. Thats why I don't own any phonograph records. Like the dozens you do.
Kerr - David Hannum was taking about YOU, sport! LOL!
The sucker who bought his volume control and tweeter amp for $500 instead of the fluoride you bought? Yeah. I suppose.
Kerr - Go back and measure... listening to music isn't for you. Music is all mathematics anyway.
Strange, that's not what I'm thinking about when sipping on a scotch at a jazz club. Well, at least until I get the tab.
Kerr - And besides, all those people making truly high definition audio components
Like who? You cower and run without showing your system - which you aren't ashamed of right? Self doubt and embarrased to show how silly it is? No? Vaporware! LOL.
Kerr - are all rolling in dough, thanks to "voodoo-ists" like me.
This is a source of pride? It pleases you to make charlatans rich? Thankful that your mind is affected by voodoo? How strong it must be.
David Hannum could never have been referring to you. Never!Kerr - Enjoy your PA. All this stuff sounds the same anyway.
Well, until you add Shakti stones and green markers. Then *you* really hear a difference.
Kerr - Ah well, better stop before I get thrown outta here. It was fun, though. The last word is yours, Tony Manero.
Bye Kerr, your words of wisdom will be sorely missed, much like missing a sore. Feel free to post your system whenever you stop wearing panties. What's the worst that could happen? We might finally learn who these true high def mystery folks are? Do you recognize the one in the picture?
cheers,
AJ
The threshold for disproving something is higher than the threshold for saying it, which is a recipe for the accumulation of bullshit - Softky
> Right. Thats why I don't own any phonograph records. Like the dozens you do. <Dozens??? That was back in the '60's. It's in the tens of thousands now, which incidentally is why my system sucks. Had to make a choice... music or gear...when I bought an estate vinyl collection this year. I miss the tubes and planars a little, though - much less when I spin the new music.
> The sucker who bought his volume control and tweeter amp for $500 instead of the fluoride you bought? <
I'm sure I've spent much more than $500 on flouride in 49 years. It gives the sound more teeth!
> Strange, that's not what I'm thinking about when sipping on a scotch at a jazz club. <
Now you are speaking my lingo! What jazz, what jazz club and what scotch? All three make audio gear much less important.
> You cower and run without showing your system - which you aren't ashamed of right? Self doubt and embarrased to show how silly it is? <
Not ashamed of it exactly - and it's anything but silly. It was my former second system and it's nothing to brag about. So I don't. If by asking to know my system, you're really wondering about my audio sensibilities they are tubes, vinyl but I still own and love my many CD's, planar speakers, high definition wire, no power conditioners, no aftermarket power cords, although I did try the latter. No Bedini Clarifiers, no CD treatments, no cable elevators. Perhaps I'm only a pseudo-voodooist. A voodooist wannabe?
> It pleases you to make charlatans rich? <
That was me being facetious! With the exception of Noel Lee, how many audio gear manufacturers are rich? Sheesh, my whole last two posts were nothing more than teasing - an attempt to show you that you're not special by acting like a condescending asshole... ANYONE can do it. I'm not one and I'm betting you aren't, either. So why act like one?
> Well, until you add Shakti stones and green markers. Then *you* really hear a difference. <
I actually tried the green markers many years ago. They have value. Ultimately I used them to write on a whiteboard at work. They emitted a rather pleasant squeak.
> Feel free to post your system whenever you stop wearing panties. <
Two possible responses:
1) I started wearing panties when my wife found a strange pair in my car's glove compartment.
2) Panties? You drink scotch. Ever try Lagavulin or Talisker? Try 'em. When you do, I will ask again - panties???? :)
xx
The threshold for disproving something is higher than the threshold for saying it, which is a recipe for the accumulation of bullshit - Softky
Glenmorangie is an excellent scotch. Can't remember if it's from Speyside or the Highlands right off but I do recall they had one aged longer than their normal run that was quite good also. Glenmorangie is one that I would recommend to someone that is enamored of Glenfiddich but wants more body and flavor without getting his head blown off.
Hey Kerr,You're a Scotch drinker? GOD bless ya. My dad was a Scotch drinker but I never could develope a tongue for it. Me? I like Gentleman Jack, from Jack Daniels. Crazy as it sounds I like sipping it slowly like Brandy, from a large brandy snifter. That way I get the same warm glow my tubes emit :^) as the Jazz musicians start to play yet again in Orlando at the Scata house.
Thetubeguy1954
When I worked in the publishing business, I used to travel to our home office in NYC the first week of each month. There was a place called Keen's Steakhouse (or perhaps, Kean's) that boasted over 150 different single malt scotches. I did not have the opportunity to try all 150 but my favorite, much like my favorite audio gear, was beyond my financial capacity for regular consumption. 30 year old Clynelish is the Jadis of the scotch world. :)> I never could develope a tongue for it. <
I think one has to have a high level of motivation to like it. It takes time. Gentleman Jack is kinder to newbies, as most bourbons have a nice sweet flavor due to the corn they're made from. Scotch is made from peet, its usage not that far removed from manure in some cases. :) It's an acquired taste that one must want desperately to acquire. Once acquired, nothing else can take its place, although I have been known to experiment with cognac on occasion.
Hey Kerr,Isn't it a shame that most here cannot talk/discuss/debate their different preferences in audio as easily & civilly as we can talk about our different preferences for either single malt scotches or bourbon? The best bourbon I've tried so far was Black Maple Hill. I'm sure there are probably much better bourbons out there, but for me, Black Maple Hill is the best I've ever tried.
Now that you got me started on it, I'll have to look it up on the internet and see if I can find any near me. Well Kerr in any event, I hope you make it doen to Orlando, Fla someday. I'd love to have you over some Scotch & Jack! We can listen to some nice mellow Jazz. Then as the tubes warm the room with their soft glow, the liquor will warm our bodies as the music warms our souls. Of course if there is a Mrs Kerr she's welcome to come as well. My wife Martha is a Colombian from Soth America. She's very gregarious and always loves company.
My best, Thetubeguy1954
...to discuss our audio differences in terms of preferences rather than absolutes. Unfortunately, most of what I've learned about the two factions of audio enthusiasts can be summed up:Subjectivist: A gullible voodooist who allows his ears to fool him and gets suckered into buying worthless items, all the while badmouthing science.
Objectivist: A bookworm with bad hearing, poor critical listening skills and/or a system without sufficient resolution to elicit sonic differences.
As it shall always be.
I certainly give the other side their due - they've got me thinking. One thing I wonder about is the "concept" of fidelity. I call it a concept simply because I think the two sides view it differently. Since it is more an objective (measurable) term than it is subjective, I wondered about how subjectivists strive for it. I think most of us don't, whether we want to admit it or not. We don't, at least not fidelity to the recording. Rather, I think we strive for fidelity to our own personal idea of what the recording SHOULD have sounded like to us. In other words, we put our faith in the musicians rather than the recording engineer. This is why low THD and all the currently known metrics are of limited value to us; we want what sounds right to us i.e tubes, vinyl, wire, etc. All I can say is that the best measuring system I ever heard sounded like garbage, even on the best recordings - ESPECIALLY on the best recordings.
What do you think, Tom? I wonder if this should be its own topic.
LOL
The threshold for disproving something is higher than the threshold for saying it, which is a recipe for the accumulation of bullshit - Softky
"EDUCATION
A four-year degree in a computer-related discipline is required for most software engineering positions.
Certification in various software applications is suggested.
Training programs are available at community colleges, vocational schools, technical institutes and in the Armed Forces."I still don't understand how this is different from just computer programming. Well, it's all on off. Ones and zeroes. go/no-go. It either works or it doesn't.
BTW, how do you sell computer software engineering? The company I worked for from 1984 to 1995 was a very large software developer. I built a lot of data centers and installed lots and lots of mainframes and networks. Their software was targeted specifically at the telecommunications industry. In fact, they were the leading supplier to the RBOCs.
There are more related responsibilities that surround the coding process."Software engineers should also be adept at debugging complex application problems and be able to produce quality software documentation, including requirements specifications, design documents and unit test plans.
BTW, how do you sell computer software engineering?
I sell the value proposition of using advanced inventory and warehouse management systems to wholesale distributors. RFID is the next big thing and there is one particular neighbor here in AR that is all over that concept.
rw
A successful joke that had 9, $3.11 drivers made at Oxford loudspeakers in Chicago and a $22 plastic enclosure, that made millions of dollars that helped fabricate the idea they were king of fidelity.
Might sound like crap but was brilliant marketing at just the right time..Tom
Apparantly Roger Russel got it. He's selling 50 similar ones in two long wooden shoeboxes and a $129 equalizer without sliders for $19,000. How many suckers will buy that one?
> Apparantly Roger Russel got it. He's selling 50 similar ones in two long wooden shoeboxes and a $129 equalizer without sliders for $19,000. How many suckers will buy that one? <LMAO! Perhaps Russell will, too! :)
Hi Kerr,You have to give Unsoundmind this much... he's an equal oppotunity hater! He distains everyone whether they are one of his fellow Objectivists, like my friend Roger or Subjectivists and everything that's better than his BSR equalizer and Citation 11 preamp IIRC equally!
I think Unsoundmind should start his own audio business. He could restore or replicate Citation 11 preamps, BSR equalizers, AR-9 speakers and whatever ancient solidstate power amp he prefers! Then he could market these systems as The Best Audio Ever Was or Ever Will Be!
Thetubeguy1954
Have you read Russell's treatise on wire and the (lack of) audibility of it? If he's a friend of yours, perhaps he would be a good contestant for your home system blind wire tests. It might make him more comfortable with his decision to use Cardas instead of junk wire.Just a thought.
One other thing - you've mentioned your Mastersound amp. Who makes this? I'm not familiar with it at all.
Hello Again Kerr,I have read Russell's treatise on wire and the (lack of) audibility of it? We've discussed it a couple of times always in a very civilized (unlike here) manner. We've never come to an agreement nor have we put it to a actual test as of yet.
Roger is a friend. In fact he extended another invitation to me via email this week to come and listen to his system. I believe he wants me to come over his place before he comes to my place but I may be mistaken. One of these weekends when I'm not hurting to badly I'll go pay a visit. Saying this is liable to incur Unsoundmind's wrath once again, but by the end of the working day I'm shot, i.e. too much pain to want to do anything but go home. I have insomnia as well, also pain related, so usually after 5 days of catching only 2 or 3 hrs sleep, I end up sleeping a lot of Saturday away. The reason why is because I don't have to function on any level, like at work, so I can dope my pain away easier (easier means without concern for what others around me are thinking) from Friday night to Sunday night. So Sunday's after sleeping away most of Saturday and taking a little extra pain meds, will usually be my best bet. If Sundays work for Roger as well, I'll have to start initiating us having a wire test.
I agree that Roger would be a good contestant for my home system blind wire tests. If I can convince him to come over it "might" make him more comfortable with his decision to use Cardas instead of junk wire. But at the same time he might insist on DBT and and ABX comparator. I'm still ok with the blind testing just not adding an ABX comparator to my system. Not at least until it's been proven to be unaudible when installed into my system.
As far as my Mastersound amp goes it made by Mastersound of Italy. It's actually called the Mastersound Reference 845. I've provided a link to all it's specs with a photo below. As always it's a pleasure to tall with you!
Here's hoping you are enjoying your system as much as I am enjoying mine! Thetubeguy1954
> I'm still ok with the blind testing just not adding an ABX comparator to my system. Not at least until it's been proven to be unaudible when installed into my system. <That is certainly reasonable.
Nice looking amp. I have never heard one nor any of their other offerings. I'm starting to look into SET with reasonably high efficiency speakers. The best amp I ever heard was a 22 watt SET made by Wyetech Labs. No way I could ever afford the $10K asking price, however... now would I be willing to give us the music software I'd have to give up to get the amp. So I'm looking for a less expensive alternative.
and surveyed the campus built by Amar's great idea. Also met a guy who worked there and validated the notion that component quality was, well...rw
Ever since I have had amps with the clipping light built in my eyes have been opened. This little feature teaches a listener how the difference sounds. To go loud with 20-20KHz response is going to take some very big power in my system. After some experimentation it has become apparent that most of the power available goes toward reproducing the lower frequencies. I came to this conclusion after noticing that I could achieve higher SPL's by raising the lower frequency rolloff frequency (by twaeking with my EQ). In my system it is very possible to make more noise by continuing to turn the volume knob but after the clip lights come on it sounds very bad to my ears. It seems the fate of a solid state amp owner is to continually add more powerful amps until the volume levels you desire are achievable without ever clipping the output signal. I am about where I want to be now @ about 1200W peak per side but I think my speakers could take more and I am considering a couple of 2.5KW per side monoblocks to see how it sounds. I like nice full bass when I turn it up.
Hi Ugly,Allow me to play the devil's advocate. From your statement "Ever since I have had amps with the clipping light built in my eyes have been opened. This little feature teaches a listener how the difference sounds." It seems that before you owned amps with the clipping light built in, you didn't hear the amp clipping. Therefore isn't it quite possible that it's only because you can actually see the amp clipping that your expectation biases are "fooling" you into believing you are hearing the differences? So now when you see the clipping light go on, it sounds bad to you because you expect a clipping amp to sound?
I'd like to see proof. For me it wouldn't even need to be a DBT with an ABX comparator that the proponents of Objective listening would normally require of such a claim. I'd be satisfied if somehow the clipping lights weren't able to be seen by you and you could still identify everytime the amp clipped. Please understand, I'm not saying that you cannot hear when the amp clips. I'm a Subjectivist at heart so I believe it's quite possible that you can. However as your ability to discern when your amp clipped only occured when you had lights informing you the amp was clipping, I'd just like to see if you could still tell with the lights not visable to you...
Thetubeguy1954
Hi Tubeguy,I will likely not be able to supply proof sufficient for anything. I am just not tooled up for that analysis at my house where my soundsystem is, and I suspect that I would not be popular with anyone if I were to drag it into the lab here at work.
What I can say is this: having the clip light has allowed me to identify an effect that has always been present in my various systems, not identify some new aspect. Especially when younger and when I would tend to "crank it up", fidelity be damned, this problem of distortion especially in the low end would become apparent. It is just that before I had the clip light all I could say for sure is that when the volume is too high things start to break up in the low frequencies. The clip light has merely allowed me to identify what has really always beeen a problem for me.
Ugly,My post was mostly tongue-in-cheek! I'm a Subjectivist at heart. I hear differences when different 12AU7 tubes or different interconnects etc are used in my amp. When I repeated that here in the Prop Head Plaza I was told by some others here that because I saw the different 12AU7 tube or interconnect etc being installed I was fooling myself into imagining I heard a difference. Or in other words in reality I most likely imagined I heard a difference when I saw the different tube or interconnect etc being installed because I expected to hear a difference therefore I was biased towards hearing a difference.
So I questioned why these same proponents of "expectation bias" didn't say the same thing about you seeing the clipping lights come on! That's why I suggested that if you saw the amp clipping, like I saw the different 12AU7 tubes or interconnects. Isn't it also quite possible that it's only because you can actually see the amp clipping that now your expectation biases are "fooling" you into believing you are hearing the differences?
You don't need to provide me with one ounce of proof. You say you can hear your amp clipping? So be it! It doesn't effect my listening enjoyment one way or the other. I honestly believe you can hear your amp clipping. I'm sorry if I seemed to be questioning you or your integrity. That wasn't what I intended.
Hoping You Are Enjoying Your Music....
Thetubeguy1954
No problem at all Tubeguy. I expect to be questioned about my results. In my opinion it is necessary for seperating the wheat from the chaff. Not sure of the history here but I can guarantee there will be differences between certain tubes and interconnects which even a deaf person can detect. It is all relative you know.Point taken about the subjective part of it and I agree that the psychological effect of too much marketting can be very dangerous thing indeed but I would like to propose to you the following which I now consider a reality: The distortion from clipping in a solid state amp is extremely easily noticeable and audible. Once you have a clip light (or perhaps even more correctly an oscilloscope attatched on the output waveforms such that the clipping can directly be observed) to teach you how the clipping sounds and under what conditions it becomes a problem it is very easy to identify. It is kind of like riding a bike in that way, once you know you pretty much just always know from then on. And it is not so much that you have learned something new it is just now you have a name for what you have always heard and been aware of and can talk about it just a bit more intelligently.
I can understand why what I have said might seem a bit foreign to a tube amp guy though. From what I have read tubes clip in a more graceful way by human perception standards and so maybe a tube amp guy might not notice what sends us SS amp guys right up the wall. You'll just have to believe me on this one I guess when I say that I think even you would agree if exposed to the situation I have in my system. It is very obvious once you see/hear it.
A few years ago, at a CES demonstration at a hotel in Las Vegas, I decided to hear the sound of 'clipping' in my power amps. Bad Idea! We had 4 of my amps driving a system of direct radiators with a total output of more than 3000 Watts, and it was about 9PM. We got out the sound meter, and most of us were pushed out of the room by the volume. Then the police came! Thank God, I had the sound meter out. I just said that we were running a test, and they went away, warning me that others in the hotel like to have reasonable peace and quiet. ;-) By the way, I could hear the amps clip on that occasion.
Imagine that. I wish I would have known that back when I was throwing all of those underage drinking parties when I was a kid. Might have saved me a couple nights in jail. lol!
It’s a frame of reference issue.
Any clipping is a departure from “pure” amplification or reproduction at least from an engineering view.
In the real world where one must be practical and subjective, then the issue is much less clear.If one listens to music or other program and makes the “single sided” judgment that at X level you can maybe hear something “not right”, one would conclude that below X amount, clipping is inaudible.
Conversely, if you alternate between unclipped and clipped and compare the sound, one finds that clipping at a much lower level is now audible in that there is a difference heard between clipped and unclipped.
The unclipped as one might guess, sounds like its more dynamic.In a similar but less abrupt way, loudspeakers ALL compress dynamically too.
When the VC wire is “hot enough”, an increase in input power actually results in a reduction of acoustic out put (Doug Button’s @ JBL’s paper on power compression)
While “normal” loudspeakers are not pushed that hard, it is a fact that the effects of VC heating begin to show up in measurements at 1 / 10 to 1 / 8 rated power.
Al of these things show up “if” you watch what speakers do at different power levels.
These “minor” things are not generally discussed because they do not help sell speakers and there is no solution other than to use a speaker at a tiny fraction of what it can do (the cost of which is unacceptable in the market place).Yet, if one has a peak reading SLM, like the B&K 2204 I have , or if one records with “modern digital” and good mics, one finds that “live”, peaks are higher than you would imagine, recordings are compressed too.
For those with good headphones or time coherent speakers that can also produce “peaks”, I have an
un compressed recording at the company web site which is an exercise in dynamic range and extended lf response. DO NOT make an MP-3 of it unless its to compare it to the Wave file, the mp-3 process ruins it even at 320K.http://www.danleysoundlabs.com/knowledge baSE.htm
Best,
Tom Danley
TS - I have an
un compressed recording at the company web site which is an exercise in dynamic range and extended lf response. DO NOT make an MP-3 of it unless its to compare it to the Wave file, the mp-3 process ruins it even at 320K.I'm looking forward to using it when I complete my new speaker system. The neighbors probably aren't :-). Perhaps I'll wait till New Years Eve?
If I'm not mistaken you favor HE with high power. I'm with you on that. The system should be barely idling at normal listening levels, but be capable of high dynamic peaks. I'll settle for (peak)120db @ 1m slightly before the drivers reach xmax (not xmech) for the design although I believe you recommend even more. No basements here see.
BTW, what is an MP3?cheers,
AJ
The threshold for disproving something is higher than the threshold for saying it, which is a recipe for the accumulation of bullshit - Softky
and can see both sides of this (contentious?) coin.1. Preferred listening levels
While I attended a handful of rock concerts at head banging levels thirty years ago, I have long since abstained from such torture. My experience parallels that of SM with most classical music averaging in the 70s and 80s rarely peaking 100 db. At least from where I sit. My usual listening habits reflect those kinds of levels regardless of what kind of music I'm listening to at the time. According to the peak reading LED ladders on the amp in my vintage garage system, I am usually running under 2 watts total with some peaks hitting 8 watts. Those wishing for louder levels will naturally require considerably higher power. My 400 watt amplifier is overkill in this situation although it does run pure class A at these low levels.
2. Musical content
There can be a spectacular difference in dynamics found in various recordings. One of my worst case scenarios (and favorite pieces of music) is Stravinsky's Rite of Spring . In this forty five minute work, there is probably a collective sum of about three seconds worth of explosive peaks that determine the maximum level I can listen with 330 watt mono amps in the main music system. More would be better. 800 watts per amp would be just about right. The most natural, authoritative, completely unstrained system in my experience used a pair of 1200 watt tube amps driving the main towers and 400 watt SS amps on the subs.
I'm of the opinion that quality for quality, more power is always better to handle the most demanding music. A little, however, can go a long way with 95% of the recordings I have.
rw
This is all through your Sound Labs, yes?se
The vintage garage system uses double New Advents.rw
There is a bit of a problem here. Studies from Dave Moulton up in this neck of the woods strongly indicate that most folks really don't like spls above 110 db in their listening room, and not only that but this appears to be in many cases independent of room size. I should also note that Dave's conclusions were done with amps rated at 250 Watts into 8 ohms.
The test in your link clearly exceeds that, in addition, loudspeakers at those spl levels very typically are rather compressed and very distorted.
d.b.
120 db is the threshold of pain cited in many texts. At that level, your body is telling you that you are being injured and to "make it stop." As you approach that level, if you don't feel pain, your hearing may already have been impaired. High SPLs reportedly create other medical problems besides hearing loss. The repeated thump thump thump of loud bass in rock can interfere with cardiac rhythm and can even affect the human immune system. Apparantly, the immune system considers this stimulus to be "other" and treats it much like an invading organism. Deliberately subjecting oneself to pain is usually considered pathological anyway. I always wonder about those guys in cars whose sound systems are so loud you can literally see their windows rattle.
The average power was reading 1 Watt most of the time, which would give 89 dB SPL by the speaker sensitivity estimate. The peak power of 240W was only on one particular track of one CD (the Rikki Lee Jones track), and that was only for an instant. So it wasn't like we were listening to 110 dB SPL for anything other than a brief instant of a cymbal crash (which actually didn't sound that loud at all). I suspect the speakers were probably compressing that peak a good bit too.
"So it wasn't like we were listening to 110 dB SPL for anything other than a brief instant of a cymbal crash (which actually didn't sound that loud at all). I suspect the speakers were probably compressing that peak a good bit too. "
I think it would be very enlightening if speaker manufacturers published the power in vs. power out at power levels other than one watt. I think we would all get to see just how limited the linearity of a loudspeaker really is at both ends of the power spectrum.
d.b.
You and I know they will never publish either, but it would be nice if speaker reviews had them.
Soundstage has recently begun publishing changes in the frequency response at different levels. See Chart 4 in the link below.
____________________________________________________________
"Nature loves to hide."
---Heraclitus of Ephesus (trans. Wheelwright)
There's a lot more that needs to be done there Pat, but I just don't think the public is particuarly intertested.
d.b.
With issues of global warming, nuclear weapons proliferation, the war on terror, the AIDS pandemic, I think you are right. Amplifier distortion is not high on the public's agenda of problems to be addessed. Why not run for office on a zero tolerance for distortion in amplifiers platform. I'll bet you'd get a couple of votes.
What a great idea; I think I'll write you in for the upcoming governors election. You probably couldn't do any worse here in Massachusetts. Do you have any objection to serving as Lieutenant Governor while I'm the Governor?
I just gave you a great straight line, don't blow it Soundmind.
d.b.
I once considered running my dog for President of the United States. Of course she was under 35 years old but in dog years she was more than qualified at the time. Considering the other dogs who ran that year, one of which won by the way, the country could have done a lot worse than to vote her in. Now I've got two more dogs and soon they will both be qualified in dog years as well. Perhaps I'll run them as a full ticket for President AND Vice President. Again the competition does not seem very challenging and I think they'd have a good shot at winning. Look at what we had the last time, the Village Idiot against a guy who couldn't tell a simple joke. Now if there's one thing my dogs can do, it's tell a good joke. Just the last week they kept me up all night with "a mongrel goes into a bar and says to the bartender....." At least if they get elected, I'll get them out of the house and have a chance for a good night's sleep for a change.
Soundstage has had more complete measurements for some time, which I like.I'd also be interested to see more measurements on turntables and cartridges (particularly distortion with those), which Stereophile doesn't measure at all.
I've never been against measurements; they're essential for any DIYer so I make my own all the time. The devil is in the interpretation and correlation to sound quality. Still learning here. ;-)
Audio magazine used to show the high end by measuring the max spl vs. frequency. It didn't show the compression but it did show how the frequency response of a speaker would get out of whack at high SPL, presumably because one driver exhibited more compression than another.
If you understood my previous post, which it appears you did not, you would understand that compression and frequency response at different power levels go "hand in hand" so to speak. Power in vs. power out over frequency and at different power levels. Take a minute to absorb that.
d.b.
If you will reread my post, which you apparently did not, you will see that I do understand this and thus the thrust of my post.
If you really understoood the basic concept of linearity, you would be advocating the use of negative feedback. Since you don't I will continue to assume that you still don't understand.
Stick to Chemistry;
d.b.
You are the one who is trying to patch a non-linear circuit with a crutch that above about 1Khz simply stops working. If YOU understood linearity you would also realize that the transfer function of a triode tube is closer to linear than either a bipolar or mosfet transistor.However; it is clear that 1)global feedback simply doesn't work well up to 20Khz. This can be seen readily in damping factor vs. frequency and THD vs. Frequency plots. Most high feedback amps show a decreasing damping factor above 1KHz and an increasing THD starting about the same frequency. 2) It appears to increase the ratio of high order harmonics (this can be shown mathematically and in practice) and signal correlated "noise" floor. Granted it is not the only culprit in this as noise and power supply hum can add IM products and muck up the sound as well as underbiasing the transistors/tubes. 3) Feedback can make the compatibility with speakers worse due to back EMF from the speaker being reinjected into the amp and reamplified. This was shown by Otalla et al in the late 70s early 80s.
So from my listening experience and based on technical analyses I have seen and measurements I conclude that in general feedback does more harm to sonics than the good it does "linearizing" the circuit. This argument of "its more linear so it must be better" is so shallow and so easy to expose when one looks behind the THD curtain. Give it a rest, we are not oscilloscopes who don't give a shit about harmonics. We are more sensitive in a lot of ways than the oscilloscope and especially to the harmonic content of distortion.
You and I both know that it is not the absolute amount of THD that is important but the harmonic and IM content of the distortion under DYNAMIC conditions. So, absolute linearity is not necessarily a requirement or the issue because an amp can be less linear in an absolute sense (say 2% THD vs. 0.1% THD) than another and yet have less AUDIBLE distortion (the 2% amp could be all 2nd and 3rd harmonics while the other has harmonics right up to 20Khz for a 1Khz sine wave). Audible linearity is the issue, Dan so stop with this linearity according to the oscilloscope is everything. I know you don't even believe that yourself or you wouldn't bang the drum that your amp makes "only" 2nd order harmonic distortion (yeah sure it does).
Damping factor over 400 hz is irrelevant, it's only a factor for controlling woofers.Slew rate is deliberately limited to 13v/usec to avoid rf damage to speakers.
Distortion is virtually non existant, inaudible under any conceiveable conditions of use. And BTW, if this isn't enough power to play your speakers at any volume you'd need without clipping, there are two more larger versions offering considerably more power.
This amplifier is unconditionally stable with ANY load and has a three year no fault warrantee. So reliable, many of the world's professionals count on it to satisfy their customers. Hardly the garage built typical audiophile junk we see selling for as much or far more and certainly not one of those feeble peewee amps so popular among the one driver horn lovers. And yes it uses lots of feedback. Performance of this high caliber is not possible without it.
There's a guy selling two of them on ebay starting at only $700! Fortunately for you, no one has placed any bids for the first five days, so you've got a great chance of making your dream come true!rw
Distortion is virtually non existant, inaudible under any conceiveable conditions of use.You're still parroting that THD is relevant? You continue to forget that some of us have actually owned Crown amps. I got over mine when I was 18 and learned better. You're what - 65? Maybe if you're lucky you'll eventually get it in your lifetime.
So reliable, many of the world's professionals count on it to satisfy their customers.
Exactly. It is the audio equivalent of a Ford F-350 pickup with a V-10 Triton engine. Powerful. Durable. Capable of heavy loads. Just the kind of high performance vehicle that can really carve the corners at Nurburgring!
And yes it uses lots of feedback. Performance of this high caliber is not possible without it.
And yes it uses lots of leaf springs. Performance of this high caliber is not possible without it.
rw
You are so dense soundmind. My point about damping factor has nothing to do with woofer control!! Besides the frequency response variations with a damping factor of greater than 10 are small enough that many other factors are much more important. Look at the audioholics article on it if you don't believe me.My point about damping factor is that it indirectly shows that the feedback is losing its "corrective" power when the damping factor drops (one of the main features of negative feedback being a lower output impedance). The subsequent rise in HF distortion also points this out.
As to whether I would like the amp...I doubt it because I don't like the sound of many many amps so statistically it is at a disadvantage.
Here is a link to some measurements done on a tube amplifier with a damping factor very close to 10. The deviations from a flat frequency response into the standardized dummy speaker load are't huge but are certainly large enough to be audible.
____________________________________________________________
"Nature loves to hide."
---Heraclitus of Ephesus (trans. Wheelwright)
Like my Sound Labs. Or Dunlavys.rw
The load is used to give an idea of the magnitude of the FR variations of an amplifier into a typical speaker load.An amp with a low output impedance will have virtually the same frequency response into that roller coaster load as into a resistor. And that includes most good solid state amps. So I don't see that you have an argument here in favor of tubes.
____________________________________________________________
"Nature loves to hide."
---Heraclitus of Ephesus (trans. Wheelwright)
and then found the best sounding amp that meets my priorities for the $$ to drive it. Speakers with linear impedance curves don't restrict the choices.rw
Well, one needs an amplifier that can drive one's speakers.Still, I already have a fairly capable amplifier that will drive most speakers very nicely. When I audition speakers, I use SS amps as a rule and I can be fairly confident that they will sound much the same as they would with mine. I've no wish to get speakers I really don't like and try to improve their sound with different tube amps. Life is too short. I prefer to find speakers that sound good with accurate amps.
On occasion, I have heard some speakers using both SS and tube amps and so far, I have preferred the sound with the solid state amp. I heard my PSB Stratus Minis with a tube amp which did nothing to improve them, though they sounded OK. Said tube amp also sounded pretty coloured with the Dali Helicon 400, which sounds quite nice with a good solid state amp with a low output impedance.
I heard a Rogue integrated with some Usher X-719 speakers and didn't like the result. I preferred the sound with a SS amp, though I still wasn't all that impressed with the speakers.
____________________________________________________________
"Nature loves to hide."
---Heraclitus of Ephesus (trans. Wheelwright)
Why do you find the +/- 1 db variation caused by a roller coaster speaker impedance load (boy look at that S2 ride!) significant yet (apparently) find the +8 / -13 db response of your speakers insignificant?
Look closely at the VTL's errors in such a load: a 1 db rise centered around 70 hz (S2 trough 2.5 db), another 1 db rise centered around 1.5 khz (S2 trough 5 db), a 1.25 db trough centered around 4.5 khz (S2 rise 2 db) and a gradual downward slope starting around 10khz (oh well can't fix the spectacular S2 peaks/troughs here). With the exception of the top octaves, it seems to me the errors are quite complementary.
rw
Let's clear a couple of misstatements up right now. First of all, it is not the alleged roller coaster impedance curve that causes the audible frequency response variations, but it is in great part the of the interaction of the output impedance of the amp with the impedance curve of the speaker.Second, I have never maintained the FR variations in speakers are insignificant, and I have no idea why you would think so. It is certainly something you have made up.
Third, as to the variations caused by the interaction of the impedances of the amp/cable and speakers, I make two basic points about that. First of all, that the FR variations of amps with a high output impedance into many speakers loads is likely to be audible, sometimes quite audible, whereas the FR of low output impedance amps varies very little into most speaker loads as compared to driving a resistor. Of course, as you pointed out, an amp with a high output impedance driving a speaker with a pretty flat impedance vs. frequency curve would change its FR much--but then, it would sound pretty much like an amp with a low output impedance!! That's hardly much of an argument for favoring tubes . . . but if you prefer tube amps, that's fine with me. I'm not trying to convert you, but appear to find my preference for solid state threatening.
A second point is that I generally audition speakers with good solid state amps (which mostly have a low output impedance). This removes a variable which is likely to be significant from the audition.
If I thought some FR shaping would improve my speakers, I would get an EQ (1/3 octave or perhaps parametric) rather than trying to try out different tube amps in the hope that something would improve. But, then I make every effort to get speakers I really like and I have succeeded in doing so over the past decades.
I'll have to suggest the same thing to you as I do to RGA: if speaker measurements don't mean anything to you, then don't bother with them.
Now, I can only tell you what I know, and there are people who know a lot more than I do about this. If you really want to find some answers to your questions about what is significant from technical people, why don't you look at Dr. Toole's White Papers? I think this is the most relevant one:
http://www.harman.com/wp/pdf/Loudspeakers&RoomsPt2.pdf
JA, who took the measurements of the Paradigm Signature S2 for Stereophile, commented that "the balance overall is impressively flat," and it is. In JA's measurements, there is no such thing as a "+8 / -13 db response" in his curves above the bass. The only thing about +8 I can see is tweeter ringing above the audible range at maybe 27 kHz (many speakers have this, even some 'stats, I think), and on axis there is a very narrow interference dip (I should guess)around 12 kHz, but not off axis. JA pointed this out, BTW, but perhaps you missed it.
Now, though I find JA's dispersion measurements to be very revealing, I think the NRC measurements are more accurate, and even JA likes to compare his results to them when a manufacturer such as PSB provides them. And the NRC measurements as shown on the Soundstage site, linked below, are in many respects extraordinarily good for a speaker, such as the Listening Window curve in Chart 2. While you might prefer the response of the S2 with a tube amp, then again you might not. In any case, if I want a more downward sloping response with some recordings, there is the Tilt control on my Quad preamp. Much handier than changing amps!
____________________________________________________________
"Nature loves to hide."
---Heraclitus of Ephesus (trans. Wheelwright)
What about the interaction of high feedback amps (like those SS amps you love because of their low output impedance) with highly reactive speakers (yep those ones with a roller coaster impedance curve)?Don't know what I am talking about?? It was described in the late 1970s and 80s by Otalla regarding the back EMF of the speaker CREATING distortion in the amplifier because the feedback loop provides a pathway for the back EMF to be reamplified. They suggest that it could be a big reason for the variability in the sound of amps with various speakers and of course in no way affects the frequency response. Low damping factor amps (usually low or no feedback) are immune to this problem and simply dissipate the back EMF as heat at the output transistor or tube.
Its not all about FR. I have done experiments where I made equalization curves for different amps to the same target. The amps still sounding drastically different...not just slightly different but the difference between finding the music interesting and boring (talking strictly about acoustic music here).
"If I thought some FR shaping would improve my speakers, I would get an EQ (1/3 octave or perhaps parametric) rather than trying to try out different tube amps in the hope that something would improve. But, then I make every effort to get speakers I really like and I have succeeded in doing so over the past decades."
Different amps are NOT about tailoring FR because even most tube amps will have little effect on the FR response. Its about tailoring the DISTORTION response, specifically going to an amp that has less audible distortion vs. one with more audible distortion.
"Now, though I find JA's dispersion measurements to be very revealing, I think the NRC measurements are more accurate, and even JA likes to compare his results to them when a manufacturer such as PSB provides them. And the NRC measurements as shown on the Soundstage site, linked below, are in many respects extraordinarily good for a speaker, such as the Listening Window curve in Chart 2. While you might prefer the response of the S2 with a tube amp, then again you might not. In any case, if I want a more downward sloping response with some recordings, there is the Tilt control on my Quad preamp. Much handier than changing amps!"
The tilt control doesn't change the distortion character of the amp and so the same audible problems remain. Likewise, a FR measurement says nothing about driver and cabinet colorations, response decay measurements (ie. waterfall plot), distortion, thermal compression (which affects dynamics and tonal balance at different output levels), diffraction effects etc. etc. all of which contribute to the final speaker sound. Driver and cabinet noise can be riding as little as 10db below the main signal in the worst case. Thermal compression can cause all dynamic peaks to be truncated for one driver over another (low sensitivity drivers heat up quite quickly), resulting in a tonal balance shift on peaks and/or sustained high levels. Distortion at crossover points is common and if that point is in the 1-4khz range possibly quite audible. High Q resonances in the cabinet and port store energy that smears later signals. All of these dynamic effects have just as much impact on the sound as FR.
This is why the Wilson X1 Grand Slaam sounds terrific with a great amp even though it has a far from perfect frequency response. Dynamically, the speaker is very well engineered. Freedom from cabinet colorations at all levels, lower distortion than most amps, no thermal compression at sane listening levels, low order crossovers so low Q circuits and thus no ringing, low Q tuning on the bass system etc. etc. Just about the ONLY thing it does wrong is FR and we both know that this is easy to fix these days.
In JA's opinion, my speakers are not particularly difficult to drive. Are you seriously trying to maintain a Quad 606 can't handle them?morricab
"Its not all about FR. I have done experiments where I made equalization curves for different amps to the same target. The amps still sounding drastically different...not just slightly different but the difference between finding the music interesting and boring (talking strictly about acoustic music here)."How closely did you equalize the FR of the different amps? What controls did you use? What were the blind test results?
I could ask the same questions about your comments on distortion. Do you have audibility data?
I've never heard the Wilson X-1 Grand Slamm. Collom's displays are quite different from JA's, I must say. The FR results in Stereophile don't look all that bad, though Colloms' curves are more smoothed than JA's, and the dispersion isn't bad, either.
____________________________________________________________
"Nature loves to hide."
---Heraclitus of Ephesus (trans. Wheelwright)
"In JA's opinion, my speakers are not particularly difficult to drive. Are you seriously trying to maintain a Quad 606 can't handle them?"Name? What are these wonderful mystery machines? The Quad 606? Whatever floats your boat.
"How closely did you equalize the FR of the different amps?"
The limits of the RTA are around 0.2db and I try to keep each band within 0.5db of each other. This is measured in room with pink noise with a microphone at the listening position. This is about as close as one can reasonably do without a TACT.
"What controls did you use?"
Not sure exactly what you mean here? A blank? I can bypass the equalization with the push of one button. There is no blank in this situation because SOME amp has to be driving the speakers or there is no sound at all. What controls do YOU use? Do you even equalize your system? How many different amps have you tested with NO equalization?
"What were the blind test results?"
Tests were not conducted blind. Results are based on long term listening impressions. I have done single blind tests with preamps and the results were pretty conclusive that differences were easily audible...I would expect the same with amps but it is far less practical with amps.
"I could ask the same questions about your comments on distortion. Do you have audibility data?"
I made a test cd of solo violin with distortion added as per the software that Keith howard made available after his stereophile article. Most of the added distortion was audible compared to the undistorted original but certain types were clearly less pleasant than others. The original undistorted was the preferred track.
There have been published studies on the audibility of distortion. I don't have them immediately avaiable but if you search I am sure you will find some.
The X1 is not a terrible measuring speaker but it is far from the flattest. I have seen $500 speakers with a flatter FR and that was my main point that this flat measuring $500 speaker sounds far worse than an X1 even though its FR is far better.
A basic technical control is level matching. I would think using a volt meter at the speaker terminals would be a better way of matching levels than your method. The audio clubs long ago discovered that when decent amps were EQ's to within .1 dB, no one managed to prove under blind conditions that they could tell the difference as long as the amps were in the operating range. When you can do that, then maybe you'll get some results that others might take seriously enough to want to replicate.morricab
"Name? What are these wonderful mystery machines? The Quad 606? Whatever floats your boat."Hummmphhh! You have chosen to comment on my speakers without knowing what they are. Under the circumstances, I see no reason to tell you. There's nothing mysterious about them. E-stat knows and you could look them up just as easily as he could. I suggest Inmate Systems.
Quad 606. Well, I like it, and it can drive most speakers quite well, as can lots of other amps.
____________________________________________________________
"Nature loves to hide."
---Heraclitus of Ephesus (trans. Wheelwright)
"The audio clubs long ago discovered that when decent amps were EQ's to within .1 dB, no one managed to prove under blind conditions that they could tell the difference as long as the amps were in the operating range"Proof? Show me don't tell me.
"You have chosen to comment on my speakers without knowing what they are"
What? Calling them wonderful mystery machines? Not much of a comment really. I can't access inmate systems from work (it is blocked). Maybe I will look when I am home.As to the Quad 606...whatever.
This is the comment you made, and I already linked the post:morricab
"I shudder to think how bad your speakers must be if you can't hear the difference between a good tube amp and a crown amp."
____________________________________________________________
"Nature loves to hide."
---Heraclitus of Ephesus (trans. Wheelwright)
Well maybe if you told me your speakers I would no longer think it was your speakers that can't resolve the differences...just your ears.
Of course, that part of the sentence is incorrect, totally made up, not anything I have said, and I addressed that in the post below it. Of course I have come expect that sort of thing from tubeguy, E-stat, sometimes Clark, and now perhaps I'll have to expect it from you.
____________________________________________________________
"Nature loves to hide."
---Heraclitus of Ephesus (trans. Wheelwright)
I see now why you are obssessed with NRC measurements and FR response because you own paradigms. I was also kind of that way when I owned them because afterall it is sort of the their USP. You have to believe their marketing hype to buy the speakers of course. Oh and they don't sound too bad...but not great either.What I realized along the way in this journey is that flat FR is one of the easiest things to fix and not even that important to getting a live sounding system. Transparency, coherenecy (including the time domain), low level resolution, dynamics, freedom from compression, low coloration, and low distortion are all just as important and more importantly, not correctable by DSP.
You are apparently still in that stage of the audio hobby where you think the speaker is the only or at least by far the most important part of a system. This is most likely due to the fact that you have only mediocre components in your system. Switching with other mediocre components brings no real improvement. Of course one needs a sufficiently resolving speaker to begin with. You can do much better than the Paradigm S2 (not new maybe but there are plenty of better used speakers to be found). You can do seriously better (the whole system that is) for not that much money.
What I have found is that once you have a speaker that is truly transparent, low in coloration, high in coherency (means time aligned or single driver usually), low in distortion, and highly resolving of low level information (something paradigms do not excel at doing) then the speaker no long becomes the limiting factor in your system. Gear differences become so obvious that you wonder why others even argue about it.
The NRC measurements are probably the most accurate available to me and they work pretty well for me. They are a useful screening tool, and I see absolutely no reason to consider speakers that don't measure reasonably well. Such speakers don't sound good to me. Measurements are a tool and I fail to see anything obsessive about that.As I've sometimes said before, the kind of measurements available to me can tell me what speakers not to get but they can't tell me which ones to buy.
Let's look at the factors you propose:
-Transparency: a piece of optical imagery, not really very clear in its application to audio. Some mean sonic invisibility, in which respect the S2 is excellent. Otherwise, this must require an even FR.
-coherency (including the time domain): God knows what you mean by coherency. Time and phase coherence do not seem to be that important in speakers save as they affect the FR. In any case, the S2 is subjectively very quick, and I have owned Quad ESL-63's, but they don't really fit our room acoustics very well. The S2's sound better here.
-low level resolution: I wonder whether people who use such jargon have any idea what they are talking about.
-dynamics: this usually refers to punch in the bass. Anyway, I listen well within the dynamic limits of my speakers.
-freedom from compression: Soundstage has begun to measure this and even an inexpensive PSB speaker seems to do well in this respect.
-low coloration: And you were denigrating the importance of even frequency response? GMAB But of course, the dispersion counts, too, not merely the on axis response.
-and low distortion: well, Soundstage has measured this for quite a while and the S2 does pretty well.
-Resolution is something you also mention: it's also an optical image whose applicability to audio is again not too clear. I suppose it means one can hear what's on the recording.
"Gear differences become so obvious that you wonder why others even argue about it."
Gee, I want to listen to music, not gear differences.
____________________________________________________________
"Nature loves to hide."
---Heraclitus of Ephesus (trans. Wheelwright)
Well the fact that you have difficulty understanding some generally accepted audio language makes this discussion rather difficult, or are you merely being obtuse? I assumed that at least some of these definitions are obvious and at least a few have been explained and discussed enough that you know what I mean.However; I will address the points and give you what I am thinking about when I use these terms.
1) I never said even frequency response wasn't important, just less important than you give it credit because of its relative ease of correction. With modern DSP, FR is the least of a speaker designer's worries.
2) Transparency "a piece of optical imagery, not really very clear in its application to audio"
You are the only one who would question this. Yes it is an optical analogy but one that is quite clear (no pun intended) to most people because the auditory equivalent is the feeling that there is nothing between you and the original sound. It mainfests itself in that on recordings with natural acoustic one can hear the ambience in the recording clearly, for example. In this sense it is related to low level resolution but low level resolution also includes clearly perceiving subtle dynamic shifts at low levels, not simply did you hear the sound or not. Does the character of the instrument retain the correct timbre and expression at that low level or is it indistinct?
3) Coherency: The sense that the sound is coming from a unified source and not multiple sources. Nearly every box speaker betrays the drivers it uses to make sound. This is due to crossover anamolies, differing driver materials, sharp cutoff, cone resonances etc. Time coherence is another matter and why I put it in parenthesis. It has been my experience that speakers which are time coherent (for example full-range electrostats or a speaker like the Thiel CS3.6) are also more coherent in the first sense of the word. An example of one of the least coherent speakers I know is the B&W 802N. This speaker uses a different material for each driver and high order slopes. Hearing the transition between drivers is painfully obvious as a change in the coloration of the timbre of instruments. It has very little to do with FR.
4) Low level resolution: see point 2 above. I will repeat, it is not just if you can hear a soft sound or not (although with some speakers and systems this is an issue) but if that soft sound retains the complete characteristics of the thing making the sound, including dynamics and timbre. MOST speakers in the world have problems at the low level sounds. Nearly all conventional medium to low sensitivity speakers fail miserably.
Example: Some friends of mine have Apogee Scintillas. These are very high resolution speakers; however they are a bit old and one friend has had them rebuilt and the other has a stock pair. They did a speaker cable test (quite important with a 1 ohm speaker) comparing the Speltz anticables to some DIY silver cables. They did this test on the rebuilt Scintillas that have the same DIY silver cable as internal wiring. They had a track of a new woman singer from Norway done in what seems to be a home studio. On one track they noticed very quiet in the background a dog barking(presumably outside the studio). They had not noticed this with the anticables but it was clearly audible with the silver cables. When they went back to the anticables and listened carefully for the dog THEN they heard it. However; it was much less distinct and barely noticable as a dog. Back to the silver cables and the dog was distinct with timbre of its voice and probably even would be recognizable to the owner. Oh they were using only 1/2 meter long cables and this was still obvious.
The other friend took the recording home on his stock Scintillas, which are wired with 20 year old Monster cable and he has 3 meter speaker cables. He couldn't hear the dog at all!!! It was simply not there no matter how hard he tried to hear it and even knowing exactly where it came in. Clearly information was being lost and now he is going to have his speaker cables shortened and rewire his speakers. This is an obvious example of what I mean by low level resolution.
5) Dynamics. This has nothing to do specifically with bass. Does a trumpet's blast rely on bass response? What about a Cymbal crash? Dynamics has to do with a speaker's or system's ability to go from one level to another level with lifelike speed and in the case of big amplitude shifts do so at ALL frequencies equally and without compression. Not just bass. Speakers that are restricted in dynamics in some frequency band will exhibit a certain "character" that is not obvious from a FR measurement (same is true for amps and sources). If a speaker sounds "dark" even though the FR is nearly flat then it suggests that the high frequencies don't have the same dynamic character as the mids or bass. If it sounds bright and the response is relatively flat then it is possible that the bass driver has begun compression whereas the mid and tweeter have not.
"Anyway, I listen well within the dynamic limits of my speakers"
Do you? Probably if you listen only to compressed music then you are right. If you listen to relatively uncompressed jazz or classical then I doubt it.
Let's be clear: Dynamic range is not just about how loud something can play. It is also about how SOFT a speaker can play and retain the correct character of the instruments (see my thoughts on low level resolution). The key word here is RANGE. From soft to loud not loud to louder. If you listen to an orchestra at REALISTIC levels then how good is your system through the soft passages and does it make it through the loud ones uncompressed? That is what I mean by dynamics and dynamic range.
6) Freedom from compression: Soundstage's measurements are steady state and not necessarily indicative of dynamic conditions.
I have seen studies that show 86 db/watt drivers that begin to show the effects of thermal compression as low as 90 db. Normally, doubling the power gets you 3db more output from the speaker. What they found was that above 90 db or so they were getting only about 2 db per doubling of power and then at higher levels only about 1 db. Eventually the driver will cease to get louder and you will probably melt the voice coil. VCs can heat up very quickly on big sudden peaks and are relatively slow to cool down thus affecting the signal that follows the big transient. This is called hysteresis and its reality is that big dynamic peaks DO compress for most drivers and at lower volume levels for lower sensitivity drivers. Tweeters are often much higher sensitivity than woofers in normal speakers. Many speakers get edgy sounding when pushed. Is it distortion?? Maybe. Cone breakup? maybe or maybe its also a momentary imbalance between the outputs of the drivers due to thermal compression.7) Low coloration: This has very little to do with FR so I am not sure why you bring it up. Coloration is the sound the speaker makes by itself when the drivers are in motion and is correlated with but not a part of the actual signal that was put into the speaker and what the drivers are putting out. This manifests itself as: Harmonic distortion, driver flexing colorations, cabinet energy storage and release, crossover anamolies, resonances etc. This altogether can be thought of as "self-noise" or the noise the speaker makes itself that is not part of the original signal. It rides typically 10-30 db BELOW the main FR and rarely, with exception of strong resonances, makes a noticeable impact on the FR. However; it is most definitely audible and probably one of the main reasons that two speakers, even perfectly corrected for FR can sound very different (along with dynamic behavior).
Often, the lower the speaker's "self-noise" the better that speaker will retrieve low level information while retaining the proper character of the sound. Transparency and natural soundstage will also improve (assuming the recording is made in a natural space). Most speakers are so "noisy" that most people don't even realize that all that garbage is riding along until most of it is gone. This relative lack of "self-noise" (all speakers have some) is one of the reasons (along with freedom from compression and dynamics) why big Wilson speakers (like the MAXX and X2) can sound quite lifelike despite their relatively poor FR.
8) "Resolution is something you also mention: it's also an optical image whose applicability to audio is again not too clear. I suppose it means one can hear what's on the recording."
See points 2 and 4 its not just what's on the recording but if the correct character of that thing is properly preserved. When I say high resolution I am also including the other points like dynamics, coloration, and transparency. Clearly there is some overlap in the terms and some terms are used in the definition of others. We use optical analogies because they are ones that are easier to understand. It is not easy to describe hearing phenomena.
""Gear differences become so obvious that you wonder why others even argue about it."Gee, I want to listen to music, not gear differences. "
This is a disingenous statement and a cop out because obviously in this discussion we are talking about how the gear affects our perception of music. A high resolution speaker will give you insight into which gear and cables are giving you the full information and which ones have audible problems. However; if the speaker is mucking things up too much then the ability is flawed. You can still hear differences but it becomes more difficult to tell different from right or wrong.
The right speaker and right gear will give you more of what is on the recording and presuming the recording is a good one then more music.
I've heard much of the jargon in the audio subculture. Sorry, I just don't think most of it makes sense.I may or may not be the only one who questions the use of optical imagery in audio. For example, we have an idea what transparent means in relation to glass. It means you can see through it. Now, in audio, you explicitly relate it to feelings: "the feeling that there is nothing between you and the original sound." Nothing objective there.
Ah yes! The B & W 802N, a speaker I have heard and which certainly is not invisible. I didn't like it, either. I suspect the uneven off axis dispersion below the crossover between the midrange and the tweeter is one fault. When one talks of FR with speakers one must really include dispersion as well.
As is clear from my Inmate Systems entry, I listen mostly to classical music.
I'm so far not into DSP.
I don't know about barking dogs. Don't usually hear them at concerts. Sounds like a noise floor issue to me but then we really don't know what is going on. And you never will as long as you continute with your 'black box' approach of simply swapping pieces. I should also point out that, even as stated from your own perspective, you have not traced the problem to speakers. Do you mean that the barking dog can't be heard on other speakers?
I am simply astonished by your assertion the FR has little to do with coloration! You put it down to distortion. In any case, the distortion of my speakers is quite low at normal listening levels.
Dynamics--well Soundstage is beginning to measure compression, and did so with this inexpensive but nice measuring speaker:
http://www.soundstagemagazine.com/measurements/speakers/psb_image_t45/
Low level resolution seems to have a lot to do with Fletcher-Munson effects, also noise levels.
There are a number of things I can think of that effect whether a speaker sounds harsh at high levels. Fletcher-Munson effects can do that, too, among other things. So we haven't gotten totally away from FR.
"A high resolution speaker will give you insight into which gear and cables are giving you the full information and which ones have audible problems. However; if the speaker is mucking things up too much then the ability is flawed."
Well, there we are into optical imagery again. I'm afraid that a 1 ohm speaker will help create problems with a lot of amplifiers which can't drive it. I can't see that that makes it particularly revealing otherwise, or that it has much applicability to speakers designed more sensibly. If I wanted to drive Apogee Scintillas, I would get much bigger amp amp with lots of current capability. But my amp seems quite adequate to drive most speakers, including the Quad ESL-63 and my Paradigm Signatures S2's. I fail to see, for example, that the speakers are mucking things up just because less powerful amps can drive them.
____________________________________________________________
"Nature loves to hide."
---Heraclitus of Ephesus (trans. Wheelwright)
"Nothing objective there"
Not so. It is an observation based on what one is hearing. This can be quite objective and reproducible. Not all complex reactions to what one observes can be easily described in language. This is why we use visual analogies becuase language is far better at explaining visual observations than auditory ones. This is probably because human vision is a more highly developed sense and thus more directly related to our survival."When one talks of FR with speakers one must really include dispersion as well."
I am always referring to room response...never simply on-axis response.
"I don't know about barking dogs. Don't usually hear them at concerts"
You miss the point. I doubt it is noise floor in the conventional sense. I have heard his system and there is no hiss or hum.
"And you never will as long as you continute with your 'black box' approach of simply swapping pieces"
I have no "black box" approach just by swapping pieces. I think about the why and then think about which pieces are most likely to affect that. This is also what my friends have done with regard to the wire. See the problem is that you invalidate observation and experiment as invalid tools for making a correct sounding hifi system and I tell you that it is essential to having a correct sounding system. You observe a phenomenon, change a thing, then observe again. Eventually, insight can be had without having to change all the time. This is experience from experiment and observation...something you seem hell bent on denying yourself. My friends and I are careful observers and not afraid to find the root cause.
"Do you mean that the barking dog can't be heard on other speakers?"
That is one possible implication. It is also possible that the other friend's system is lacking resolution elsewhere. If he swaps the wiring and finds the dog barking is still missing then obviously the problem was not simply the wiring, although replacing 20 year old copper wire that is probably not oxygen free and therefore corroded is not a bad idea.
"I am simply astonished by your assertion the FR has little to do with coloration! You put it down to distortion. In any case, the distortion of my speakers is quite low at normal listening levels."
That is not what I said. It does of course affect timbre of instruments but again it is easily correctable so who cares. I don't put it down to distortion in the sense you are thinking of distortion, ie. Harmonic distortion. By this measure, most modern speakers are quite low in level and harmonic order. I am talking about NON-harmonic distortions, cone self-noise, cabinet energy storage, port resonances, thermal compression, dynamic compression etc. etc. Paradigm doesn't specify these things and therefore you have no idea if your speakers are low in this kind of distortion or not. You seem very obtuse about these very important aspects of speaker design.
"There are a number of things I can think of that effect whether a speaker sounds harsh at high levels. Fletcher-Munson effects can do that, too, among other things. So we haven't gotten totally away from FR"
No one is suggesting that FR is not an issue. In fact it is probably momentary, ie. during peaks, FR imbalances that make things sound bright or dark. This issue though isn't the FR but what causes the FR to become imbalanced? This goes back then to compression and the like. FR is the symptom in this case not the cause. The speaker might measure flat at a constant level but heat up the woofer VC and how it behaves differently from the tweeter, which has a different thermal compression curve, not to mention a different amount of energy being put into it.
"A high resolution speaker will give you insight into which gear and cables are giving you the full information and which ones have audible problems. However; if the speaker is mucking things up too much then the ability is flawed."
Well, there we are into optical imagery again. "
How so? I see no optical imagery in that quote. Resolution is a general term not necessarily related to vision.
"I'm afraid that a 1 ohm speaker will help create problems with a lot of amplifiers which can't drive it."
Maybe so but we are talking about changing cables with the same amplifiers that ARE capable of driving it.
"I can't see that that makes it particularly revealing otherwise, or that it has much applicability to speakers designed more sensibly."
What about ultra low mass, low coloration, low distortion drivers with essentially NO thermal compression (only dynamic compression at high levels)? This means the speaker retains the same character over very wide dynamic range (particularly as you go down in level). This is what the Scintilla brings to the table along with a pretty smooth FR. The character is maintained even at very low drive levels...something most dynamic speakers fail miserably at (including paradigm). Normal suspension cone drivers have to much resistance to motion at low input levels (overcoming surrounds and spider mechanical resistances necessarily limits what input signal gets a motion out).
"I fail to see, for example, that the speakers are mucking things up just because less powerful amps can drive them."
You fail to see this because no one said this. I am generally an advocate for lower powered amps anyway. I see the fact that the Scintilla needs a high current amp as its one true weakness. Its why I like other, easier to drive Apogees better overall.
A speaker mucking things is not directly correlated to its ease of drive. Lowthers muck things up pretty badly in a lot of ways: poor FR, no bass, highly colored "paper" sound. However; they are highly efficient (100db watt), which means that they move a lot with very little input and thus do superb low level reproduction and within their limits are highly dynamic. They have the opposite problems of most conventional speakers that get the FR right and maybe have less coloration but are really undynamic sounding because they don't play soft well nor do they play loudly well.
You just told me that the “auditory equivalent” of transparency “is the feeling that there is nothing between you and the original sound.” There is nothing objective in that definition and it says really nothing about the equipment or its performance but about feelings.I also fail to see that I have denied anything in your observations. Hearing a barking dog seems off hand a fairly unambiguous thing. I do wonder about your explanations, though. Here is one of the things you said about your methodology: “I think about the why and then think about which pieces are most likely to affect that.” You still don’t know technically why the barking dog is heard in one case and not another. What on earth is that wire doing? You don’t really know and that’s why I call it a black box methodology, although perhaps “plug and play” would be more appropriate. Plug and play is suitable for some types of problems, of course, like troubleshooting by a process of elimination.
"Dynamic" seems to mean different things to different people. There's one fellow here who touts his speakers, which have a hump in the upper bass to lower midrange area, who then regards some other speakers which are capable of pretty high output in that area as undynamic. Parenthetically, I think a driver is much more likely to heat up on steady signals than short transients--in the old Audio magazine, they tested some speakers up to over 10,000 watts in the tweeter range--which they surely could not stand continuously.
As for resolution, well, I’ve read high end reviews for quite some years and I am aware of some of the kinds of things that are said. Just because an amplifier isn’t suitable for driving a very difficult load such as that of the Apogee Scintilla doesn’t mean it’s deficient for driving lots of other speakers. But I’ve seen reviewers try to extrapolate from the performance into a very difficult speaker load.
But let’s stick to the barking dog. I wonder just how far down that barking dog is? It would be interesting to measure for that could raise some interesting possibilities. I could conceive of scenarios having nothing to do with cables. You compared two expensive cables—how about some 12 or 14 gauge speaker cable from the hardware store? Would the barking dog still be audible?
As I understand it, you propose that dynamic drivers have enough resistance to moving that they are likely to muck up low level signals. Now, that at least is a testable hypothesis and perhaps you should test it. It should be measurable. If you want anecdotes, I can turn the Quad preamp down to its lowest level and I still get a lot of detail and stereo spread--actually with any of the main speakers I have had: the old Kef 104s, the Quad ESL-63s, the PSB Stratus Minis, and the Paradigm Signature S2s—that old Quad 606 is very clean at low levels. I don’t have the CD with the barking dog in the background so I can’t test this (I might not even be interested in the music).
I do wonder how a speaker can maintain the same audible character at extremely low levels without something happening to counter Fletcher-Munson effects. The Quad ESL-63, for example, isn’t linear in the bass at higher levels, that is, it starts limiting itself in the bass at more than moderate levels. So we get more relative bass at lower levels. The Kef 104 or 104aB is quite robust in the bass and laid back in the upper midrange, and it also played very nicely at very low levels.
____________________________________________________________
"Nature loves to hide."
---Heraclitus of Ephesus (trans. Wheelwright)
"You don’t really know and that’s why I call it a black box methodology, although perhaps “plug and play” would be more appropriate. Plug and play is suitable for some types of problems, of course, like troubleshooting by a process of elimination.
"Well in this case that is probably what is needed because 1) In order to develop a model of how electrical signals propagate down a wire one needs an appropriate model. I guess the work of Malcolm Hawksford is a good place to start (although Jneutron might not agree). 2) I need detailed information on the metallurgy and design of the wires. This information I largely do not have.
So I can't really tell you mathematically what is going on with the wire, can I? I COULD maybe measure the signal loss at various frequencies through the wire, IF I had such an analyzer. If I was a serious cable manufacturer I would have such a thing. As I am not, I don't have one. Neither do most audiophiles. So since I can't really measure the cable I guess that is out of the question also.
I plug and play and use the analyzer between my ears. Its very sensitive and has the ability to be quite specific but it has problems with reliability and reproducibility, which is why it requires long term exposure to be certain of real effects vs. imaginary effects.
However; hearing a dog, that presummably was supposed to be on the recording and maybe wasn't heard by the engineer making the recording, and then not hearing the dog or that it flies below normal detection is something that is repeatable. It is also something clearly related to the passing of low amplitude signals.
As the only part of the chain that was changed, it seems obvious then that one can lay the blame at the cable. Plug and play or I prefer trial and error, is a perfectly valid way to test such a thing. Using a human detection system (ie. ears/brains) is a valid way to determine the audibility of such a thing and/or its relative realism.
""Dynamic" seems to mean different things to different people"
That's the problem, dynamic means one thing. If people use it incorrectly that's another issue. I expect you to use it correctly.
"Parenthetically, I think a driver is much more likely to heat up on steady signals than short transients"
I will try to find the sources but I don't think this is correct. A light bulb sure heats up and glows pretty darn quickly don't you think? A big surge of current will heat up a coil instantly but it will cool down only as function of the airflow and the coil materials.
"As for resolution, well, I’ve read high end reviews for quite some years and I am aware of some of the kinds of things that are said. Just because an amplifier isn’t suitable for driving a very difficult load such as that of the Apogee Scintilla doesn’t mean it’s deficient for driving lots of other speakers. But I’ve seen reviewers try to extrapolate from the performance into a very difficult speaker load."The Scintilla is a very special case because no other speaker is as brutal on an amp. Most of the amps that work without dying are not very good sounding as revealed by the brutal (in the resolution sense) Scintilla. So in effect it is a doubly brutal speaker. Amps that would sound good on it won't drive it and the amps that can drive it generally don't sound so good. We have now found some exceptions and a tube amp is in the works (really a 1 ohm tube amp!!).
"But let’s stick to the barking dog. I wonder just how far down that barking dog is?"Good question. I will be getting a copy of the cd soon. I hope I hear the dog on my system!!
"I could conceive of scenarios having nothing to do with cables. You compared two expensive cables—how about some 12 or 14 gauge speaker cable from the hardware store? Would the barking dog still be audible?"
Under the circumstances of this test I don't know how it could have been anything else. They were the only variables changed in the test (the first test where they heard the sound in both but greatly diminshed in one vs. the other cable). The other system could have multiple explanations (like cd player, preamp, amp, speaker's internal wiring, ambient noise). Sure they could add cheap 12 gauge wire to the test next time, why not. Maybe the dog is MORE audible! I for one am not a proponent that cables need to be expensive to be good (I personally don't have expensive cables).
"I do wonder how a speaker can maintain the same audible character at extremely low levels without something happening to counter Fletcher-Munson effects."
It doesn't matter because your brain already knows what things SHOULD sound like at low levels. Fletcher-Munson works with real sounds as well. The change heard with speakers at low levels is ON TOP of the usual changes in how you hear with level. Loudness curves on stereos in the past were to combat the problem with the stereo systems behavior not your hearing mechanisms behavior. So a stereo system that maintains the correct response, FR wise and dynamically will sound natural because the instruments sounded more or less that way live and that is what you are used to hearing from real sounds.
"The Quad ESL-63, for example, isn’t linear in the bass at higher levels, that is, it starts limiting itself in the bass at more than moderate levels. So we get more relative bass at lower levels"
This is a dynamic range limitation of the Quad-63 and means that the speaker is probably more correctly balanced from low to middle volumes. This is true for a lot of electrostatic speakers. However; some have a much higher range upward while maintaining the downward range (Soundlabs and Acoustats come to mind here) because of their nearly massless drivers.
"The Kef 104 or 104aB is quite robust in the bass and laid back in the upper midrange"
Then it likely had a dip in the FR through the presence region, which once corrected with equalization, it would no longer sound so laid back. OR it has some dynamic constriction at the top of the coaxial midranges passband or some funny breakup modes? How good is its balance at low levels compared to a top electrostatic speaker? That is the question.
The old Kef 104 was pretty flat in the listening window but with the 8" woofer crossed over to a 3/4 tweeter at 3 kHz the off axis response suffered between about 1000 and 2500 Hz, which would affect the total power response. You can't really fix that with an equalizer, though it can help things to a degree, as it won't improve the dispersion. It was quite a good speaker in the right set up, but not really room friendly. Compared with the Quad ESL-63, it really didn't sound bad at all, but not as detailed.The ear is less sensitive to both low frequencies and high frequencies. This has nothing to do with the deficiencies of stereo systems. It's easy to look up on the net.
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"Nature loves to hide."
---Heraclitus of Ephesus (trans. Wheelwright)
"The ear is less sensitive to both low frequencies and high frequencies. This has nothing to do with the deficiencies of stereo systems. It's easy to look up on the net."THat's my point! In real life with real live instruments your hear sensitivity also drops at high and low frequencies with decreasing level. When we hear the highs and lows dropping out with a stereo at low levels its because there is EXCESS loss over and above our normal lack of sensitivity in these ranges. THis loss is coming from the stereo itself. If it were to maintain the same FR and dynamic envelope at 50db as it has at 80 db then the softness would sound natural as when an instrument gets softer from 80 to 50db. Since most stereos don't sound natural at low levels this is a clear indicator of excess loss from the stereo not because of the change in hearing sensitivity. Loudness contours were designed to overcome the limitations of the gear not the listener. Your brain knows what sounds natural at low levels and so the hearing curve is irrelevant for live sounds. If the response of the stereo system is constant regardless of level then the sounds on the recordings will soften in a natural sounding way but most systems are not constant thus the loss of realism at low levels (and high levels).
Well, just from a layperson's point of view, I think it's a little more complicated than that. First of all, we have your idea of "natural" sound, which has not been verified. Second, in real life, sounds farther off are often softer but have more reflected sound. Third, turning the volume down often makes the stereo image seem to move back some. Fourth, like it or not, at lower volumes, the ear is less sensitive to low and high frequencies.Many posters here besides my self have suggested that speakers which sound good at low volumes tend to approximate the Fletcher-Munson curves (or someone else's equal loudness curve).
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"Nature loves to hide."
---Heraclitus of Ephesus (trans. Wheelwright)
"First of all, we have your idea of "natural" sound, which has not been verified"True and the same can be said for when you say your system sounds fine as well. However; are you a regular goer of live classical and/or other music that is unamplified? Are you a musician or have you lived with someone who is a professional musician? Do you now or have you ever been involved in the making of recordings in natural spaces (ie. a concert hall)? If you answer yes to these then I perhaps we are coming from the same background.
"Second, in real life, sounds farther off are often softer but have more reflected sound."
Yes this is correct; however, we are discussing the systems effects on sounds that were recorded from farther away or that are soft but close. You don't want the system to impose the same effect as a live sound from far away. It is like a double negative, its a no no!
"Third, turning the volume down often makes the stereo image seem to move back some."
Why should this be? Is this simply your observation in your system or do you have some physical explanation? If the system is properly preserving the harmonic content of the instruments when you decrease the volume then it shouldn't happen. With a real instrument, like a sax or trumpet, the sound recedes more inside the instrument at lower volumes than when it is played full blast. This has a lot to do with how the harmonic content of the instrument changes with the volume level its played at.
If I understand you correctly you are saying that a loud trumpet (as it is on the recording) played back softly (as in the volume control turned down) will sound farther away than it would if the volume control was set to give a realistic SPL level. IMO, this is a clear sign that your system has a different set of harmonic components that it adds at the low level vs. the high level or the speakers FR balance is different at low spl level vs. high spl level. Either way this would seem to indicate a problem with that system. I don't disagree that this receding of the sound with decreasing level could happen just that it should not happen.
"Fourth, like it or not, at lower volumes, the ear is less sensitive to low and high frequencies."
No one is disputing this. However; the microphone doesn't suffer from this problem, which means that soft sounds are captured with close to the original harmonic content and freqeuency balance. The reproduction will then sound natural (ie. you will hear the same content on the recording that you would have heard live if you were there) IF the system is not further altering the harmonic content and FR with level. If it is, namely losing bass and HF response at low levels, then the sound will lose life at low levels and no longer sound realistic. As long as these are preserved at low levels it will sound like a natural softening not the usual lifelessness most systems exhibit.
For example, whenever a reviewer says a speaker needs some juice to "wake up" this is a clear sign to me that this speaker cannot perform naturally with low level signals, this means either when played at low volumes or when there are soft sounds (like ambient information) in the louder matrix of the music.
"Many posters here besides my self have suggested that speakers which sound good at low volumes tend to approximate the Fletcher-Munson curves (or someone else's equal loudness curve)."
Maybe they are purposely designed this way to compensate for the losses that typical speakers show at low levels (the losses are always there just more noticeable at low levels where the percentage of error is larger). However; now this speaker will not sound correct at higher volumes because the bass and treble are tipped up. Manipulating frequency response is not really the answer to what is really a loss of dynamics. The only way I can think to do this in the frequency domain is with DSP where the DSP monitors the current to drivers and then applies a sliding scale equalization curve dependent on the signal level. It can be fast enough but I don't know anyone making a level dependent equalizer. Maybe a bright idea though.
It is the same problem with Class AB amps. They have zero crossing distortion that makes itself most known at low levels and is a major reason why these amps don't sound good at low levels because the distortion to signal ratio is much greater than at full power. The zero distoriton is always the same in absolute level terms.
Of course, my idea of natural sound has not been verified, either.Musician? Well, I've been a choral singer most of my life and have been capable of baritone solos for some decades. I've done some recordings. Just heard the dress rehearsal for Messiah last night (I have laryngitis, so couldn't participate). Maybe I'll be able to do some of the performances . . .
Yep. Speaker with a depressed midrange will sound that way played louder too, but that can be quite pleasant on a lot of material. But it doesn't prevent them from sounding great at low levels.
Walking away from a live performance is not the same as turning the volume down.
You'd better look at those equal loudness curves again. Sensitivity in the bass drops quite a bit as the level goes down.
When you get around to measuring the behavior of speakers at low levels I'll give your theories more credence. Perception of the distance of the sound source seems to be a controverted area with natural sounds and the sound image from a stereo system lacks many of the clues we can have with natural sounds.
Oh, I just looked on the Stereophile site and there is an interesting article by Keith Howard on voice coil heating and changes in impedance. He thinks it's likely to be a negligible factor in normal listening.
http://www.stereophile.com/reference/1106hot/
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"Nature loves to hide."
---Heraclitus of Ephesus (trans. Wheelwright)
http://www.rythmikaudio.com/servo_tech.htm
http://www.jblpro.com/pages/general_faq.htm#What is "power compression"?
http://www.nearfieldacoustics.com/whiteppr.pdf (read the section on dynamics where they state that even small compression effects in the bass can have big effects on perceived loudness).
http://www.klippel.de/download/bin\AN12 - Amplitude Compression.pdf"Don’t Make a Bad First “Compression”
All these SPL ratings are 1w/1m ratings. “But what type of performance can I expect if I apply more than 1w of input electrical power to my subwoofer?”Well, it’s quite simple: you suffer from compression. There are two types of compression to be concerned with:
1. Thermal/Power
2. BLAs electrical power is applied to a voice coil, the voice coil heats up. This causes an increase in the Resistance of the voice coil, also known as Re. This is referred to as thermal or power compression.
As the voice coil moves out of the gap, motor strength (also known as BL) begins to drop. The further the voice coil moves out of the gap, the lower BL drops. As BL decreases, output drops as well. A 30% decrease in BL will cause a 3dB decrease in acoustical output.
Now which is worse? I guess you could say that depends. Thermal/Power compression is typically a slower process. Because music is very dynamic, it does take a few seconds for the voice coil to increase in heat, and therefore, a few seconds for the voice coil’s resistance to increase. Once this voice coil is hot, it takes 10-30 seconds to cool back down. As you can see, once the voice coil has become hot, the effects of Thermal/Power compression are fairly constant.
On the other hand, BL compression is a "quicker" issue. A voice coil can move right out of the gap and back into the gap in a single second. As excursion increases, it only gets worse. It is quite obvious that BL compression is the more serious issue of the two.
Don’t Make a Bad First “Compression”
All these SPL ratings are 1w/1m ratings. “But what type of performance can I expect if I apply more than 1w of input electrical power to my subwoofer?”Well, it’s quite simple: you suffer from compression. There are two types of compression to be concerned with:
1. Thermal/Power
2. BLAs electrical power is applied to a voice coil, the voice coil heats up. This causes an increase in the Resistance of the voice coil, also known as Re. This is referred to as thermal or power compression.
As the voice coil moves out of the gap, motor strength (also known as BL) begins to drop. The further the voice coil moves out of the gap, the lower BL drops. As BL decreases, output drops as well. A 30% decrease in BL will cause a 3dB decrease in acoustical output.
Now which is worse? I guess you could say that depends. Thermal/Power compression is typically a slower process. Because music is very dynamic, it does take a few seconds for the voice coil to increase in heat, and therefore, a few seconds for the voice coil’s resistance to increase. Once this voice coil is hot, it takes 10-30 seconds to cool back down. As you can see, once the voice coil has become hot, the effects of Thermal/Power compression are fairly constant.
On the other hand, BL compression is a "quicker" issue. A voice coil can move right out of the gap and back into the gap in a single second. As excursion increases, it only gets worse. It is quite obvious that BL compression is the more serious issue of the two."
A well designed voice coil system shouldn't move out of the gap unless very long excursions are happening so thermal is the bigger problem at realistic volume levels.
Almost every speaker maker in audio is concerned with the effects and not many mention FR at all. Could it be because compression affects realism in sound more than FR abberations, perhaps?
"Yep. Speaker with a depressed midrange will sound that way played louder too, but that can be quite pleasant on a lot of material. But it doesn't prevent them from sounding great at low levels."I disagree, a depressed midrange most certainly affects things from sounding correct at any level. Speech intelligibility for one thing suffers. I have heard this with a number of speakers that have a dip in the presence region. Also, when the level gets lower that 3-5 db or so dip may now drop the response in that region below the level where the speaker performs correctly thus further reducing the clarity of sounds in that frequency range.
"You'd better look at those equal loudness curves again. Sensitivity in the bass drops quite a bit as the level goes down"Not sure what point you are trying to make here. It would be helpful if you completed the full thought rather than give a one liner and expect me to interpret what you mean. I try to be as explicit as possible so as not to be misunderstood. I frankly have now idea what you want to make of this obvious factoid. It seems like a non-sequitor.
"Oh, I just looked on the Stereophile site and there is an interesting article by Keith Howard on voice coil heating and changes in impedance. He thinks it's likely to be a negligible factor in normal listening."
I read this but I question his methodology a bit. Here is another test done with small hifi and pro monitors (not very different from the kind of speaker Howard used) and they show quite demonstrable differences in the performance due to thermal compression.
http://www.soundonsound.com/sos/jul02/articles/monitors2.asp
If you do, the least of your worries is thermal compression.
____________________________________________________________
"Nature loves to hide."
---Heraclitus of Ephesus (trans. Wheelwright)
No the average levels are that loud but the peaks could be because I often listen to wide dynamic range recordings (like 20+ db over the average level). So if it takes only a few ms to heat the coil up (one large peak) and 10-30 sec to cool it down then it is clear that thermal compression can be a problem for the music following the peak(s). The point is that the response of the system is not constant but instead constantly changing subtly. This can affect imaging stability also (for instance if the woofer in the left speaker has sublty different dynamic behavior than the right speaker woofer).
First of all, it is not the alleged roller coaster impedance curve that causes the audible frequency response variations, but it is in great part the of the interaction of the output impedance of the amp with the impedance curve of the speaker.Same thing. Speakers with linear curves don't exhibit the +/- 1 db variations.
First of all, that the FR variations of amps with a high output impedance into many speakers loads is likely to be audible, sometimes While you might prefer the response of the S2 with a tube amp, then again you might not. quite audible, whereas the FR of low output impedance amps varies very little into most speaker loads as compared to driving a resistor.
Indeed. 1 db variations are audible. 7 db variations are grossly audible.
JA, who took the measurements of the Paradigm Signature S2 for Stereophile, commented that "the balance overall is impressively flat," and it is.
We must be reading different reviews.
"The graph is impressively flat from 80Hz to 20kHz, though with slight excesses of upper-bass and mid-treble energy apparent. The former goes some way toward compensating for the S2's lack of mid- and low-bass output, while the latter is not unexpected, given my feelings about the speaker's slightly forward treble balance."
In JA's measurements, there is no such thing as a "+8 / -13 db response" in his curves above the bass.
My mistake. I was looking at the crossover plot. The summed response is only +7 / -5.
While you might prefer the response of the S2 with a tube amp, then again you might not.
Well the errors remain complementary given the extreme impedance curve. I'm not much of a box speaker fan anyway.
rw
Where is the summed response +7 -5??? There ain't no +7 anywhere near the audible range. I can see why you could misread the divisions above 10K, but I assure that high frequency tweeter resonance is way up about 27K or so, and not even you can hear it. JA didn't mention it, possibly presuming that by now readers would know how to read his graphs, but to go by your example, evidently a dangerous assumption. Anyway, here's an earlier review where JA did describe it. See his remarks above Fig. 2:http://stereophile.com/standloudspeakers/272/index6.html
So much for the +7 dB!!
Now, the -5 dB. This is a very narrow interference dip on axis around 12.8 kHz. Being very narrow and quite high, it's not very audible. As well, the dip does not occur in the off axis curves, again reducing its audibility. If you read the review, you will see that JA commented on that as well, but apparently it slid past you. Now, the research of Dr. Floyd Toole has shown that off axis dispersion affects the sound of speakers a great deal in the real world, a conclusion accepted by JA, BTW, among others. But you totally ignore that.
You also have utterly failed to see one of my points, which is that the broad modifications introduced by using using the tube amp specified would probably be quite audible--in fact, certainly more audible than that ultrasonic ringing which even you can't hear, and also more audible the very narrow interference dip around 12.8 kHz on axis. So much for the significance of the -5 dB dip, whose audibility you exaggerate.
If the impedance curves are flat, then a good tube amp and a good SS state amp should have virtually identically FR's into the speaker load. So I see no argument for preferring tubes.
____________________________________________________________
"Nature loves to hide."
---Heraclitus of Ephesus (trans. Wheelwright)
Throughout the range of 100 hz to 10khz there is more than twice the variation in the speaker response than the +/- 1 db variation introduced by the tube amp. We'll totally ignore the fact that the errors are complementary.
Where do I start? Lessee here.
+3 db at 150 hz
-2 db at 300 hz
-4 db at 800 hz
-2.5 db at 1.5 khz (entire octave from 1khz to 2khz depressed)
-2 db at 6 khz
+3 db at 10khzrw
Well, we've talked you down to an extremely narrow -5 dB dip at 800 Hz (which you have thus far ignored for some reason) and a +3 dB peak at 10 kHz . I should point out that JA's measurements of the upper bass tend to introduce a hump anyway, and that the NRC anechoic measurements give a somewhat different picture.Point one, we all know that amplifiers have smoother frequency responses than speakers. You seem to be attempting to make some point or other by repeating this, but you are far from clear as to what it is.
Oh, and by your standards, the response of the amp you showed is about +1, -1.5 dB into the simulated speaker load--I personally would ignore that narrow little dip, but since you don't, I won't. I point out that this will be audible.
Second, if you look at the NRC measurements, it is not at all clear that the variations in the FR of the tube amp into the simulated speaker load is complementary to the the on axis response for the Paradigm S2. In any case, if you prefer tubes, that's fine with me. I don't and for some reason that seems to bother you.
In any case, you have not made a very useful or significant comparions between the FR of the tube amp and that of the S2 speaker. An amplifier's frequency response is expressible with a single amplitude vs. frequency plot whereas a speaker radiates sound in all directions, and the FR in various directions is different. If the microphone moves even slightly in relation to the speaker, the FR will be different--something which is very clear in the NRC measurements and is also ascertainable from the dispersion plots in Stereophile.
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"Nature loves to hide."
---Heraclitus of Ephesus (trans. Wheelwright)
Compare that with the latest measurements from the Wilson Audio Sophia 2 and you will see that these deviations from the amp are small compared to the speaker. Are there other speakers with much better frequency response measurements? Yes there are. Are they that good in room? Not usually. Now, if you use DSP correction you are not only correcting the speaker's response but the whole system's response, rendering damping factor completely irrelevant for frequency response.I am more interested in the CHANGE in damping factor not its value.
Read this article for some more background:
http://www.audioholics.com/techtips/audioprinciples/amplifiers/dampingfactor.php
If I were to use DSP, the Crown amp would seem to be a good one. Why on earth would I want a tube amp?
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"Nature loves to hide."
---Heraclitus of Ephesus (trans. Wheelwright)
Because I am sure the crown wouldn't sound worth a damn, that's why. And if its response is so perfect, why would it matter if it were DSPed or not? You should go for it anyway. Maybe when you get the mud out of your ears and realize that the speaker is not the end all be all of sound reproduction, you will finally "get" it. I shudder to think how bad your speakers must be if you can't hear the difference between a good tube amp and a crown amp.
My speakers are Class A Restricted LF in Stereophile's Recommended Components, if you need testimony other than mine as to how good they are.morricab:
"Because I am sure the crown wouldn't sound worth a damn, that's why."How would you know whether it wouldn't sound good?
Besides, I thought we were talking about the hypothesis of DSP, in which case one would want an amp with some real guts--which tends to be very expensive with tube amps. As you point out, the FR differences would be compensated for with the DSP, assuming the amp has the guts for it.
DSP would correct the room response at the listening position, so I don't see what your point is about the speakers. However, the speakers, the room acoustics and set up, signal processing, and the program material are the biggest determinants of the sound.
How you get the idea that I would think that one can't tell the difference between tube amps and SS amps (strictly, amps with a high output impedance vs. ones with a low output impedance), I can't say. That has, after all, been proven in some cases using double blind tests--and the results of one such test was published in Stereophile, with measurements that made it quite clear why the two amps sounded a bit different on some material.
____________________________________________________________
"Nature loves to hide."
---Heraclitus of Ephesus (trans. Wheelwright)
Not for AR1,1W,3,3a,LST,10pi,11, or 9 especially if you like pipe organ music. This unit probably costs many thousands. Excellent by 1956 standards, not very good by 2006 standards. It's not on my Christmas gift wish list either. But if I saw one in the salvation army store for $50 or by the curbside.....
My point was to counter Morricab's assertion. A damping factor of 10 will likely result in audible variations in the FR with many speakers.Actually, the list price at the time of the review was $7000 USD! I could think of a lot of amps that are cheaper that would do better. But I think it would drive most speakers, though it's not a very good value for the performance.
If I were in the market for a powerful amplifier, the Crown would be a good bet.
____________________________________________________________
"Nature loves to hide."
---Heraclitus of Ephesus (trans. Wheelwright)
"My point about damping factor is that it indirectly shows that the feedback is losing its "corrective" power when the damping factor drops (one of the main features of negative feedback being a lower output impedance). The subsequent rise in HF distortion also points this out."Your statement that negative feedback doesn't work at high frequencies is just plain WRONG and for you to repeat it over and over again demonstrates you are just plain IGNORANT.
Do you know what a phase locked loop is? Every radio, television set, computer, cd player, dvd player telephone switch, even your hand held cell phone and many other electronc devices made within the last 30 years has them, sometimes many of them. They would be impossible without them. It not only depends on negative amplitude feedback but on negative phase feedback to work and it works beautifully up well into rf frequencies, by now probably well into microwave frequencies. You can rail against the principles of negative feedback all you want, it is not going away, it is a bedrock of modern electronics engineering and control systems. The prior art is JUNK.
BTW, distortion in that Crown amplifier can rise as high at 20 khz to a whopping 0.05%. in terms of sound that's less than three parts in ten thousand. Even you can't hear that, no matter what its harmonic distribution.
"BTW, distortion in that Crown amplifier can rise as high at 20 khz to a whopping 0.05%. in terms of sound that's less than three parts in ten thousand. Even you can't hear that, no matter what its harmonic distribution. "Prove it.
Do you have measurements like this one below that show what you claim to be true? Didn't think so.http://www.soundstagenetwork.com/measurements/amplifiers/belles_350a_reference/
This sums up nicely what I am talking about. If we work on the assumption that 1) Negative feedback lowers output impedance (ie. increases damping factor) and 2) Negative feedback lowers THD
Looking at the measurements it is clear that the damping factor begins to drop at around 200Hz. Likewise, the THD vs. Frequency is also increasing around this frequency. If we take the two points above then it is obvious that the negative feedback is no longer effectively lowering the output impedance and is also no longer effectively keeping the THD as low. It is also reasonable then to expect that the nature of that distortion is likely changing as well.
Far better to start with a more linear design than to "correct" to spec.
I would like to remind everyone here that Soundlab apparently has two amplifier types in operation. One is the Crown--- Big, rugged, and dutiful, like a Mac truck, and the JC-1 mono power amps rated at 800W ea. into 4 ohms. Why?
I also challenge anyone to show where this amp is modified to sound different from the signal going into it. Come on Soundmind, put your 'proof' where your mouth is.
"BTW, distortion in that Crown amplifier can rise as high at 20 khz to a whopping 0.05%. in terms of sound that's less than three parts in ten thousand. Even you can't hear that, no matter what its harmonic distribution. "
Not that it really matters, because the harmonics are all well above the range of hearing, but maybe we should ask Morricab just what the distortion is of his non linear tube amps at 20 kHz? Maybe we can expect an answer such as "the harmonic distortion of non linear tube gear is so much more musical than linear solid state gear". The late Bud Fried used to ask me all the time; "what do they mean when they say more musical"? I had a number of answers for him, but none are suitable for print.
d.b.
Dan, you will never see me write that such and such distortion is more musical than any other kind of distortion. I don't believe it and i have said so. I do believe that some distortion is more AUDIBLE than others. THerefore, the amp that is doing the LEAST amount of AUDIBLE distortion will be the better sounding amp.I am not a "subjectivist" nor am I a hard core "objectivist". I believe that he measurments and the listening are both important (the listening guiding the measurements not the other way around though).
OTL amps can for example be flat in response to several hundred kilohertz with very low distortion at high frequencies. Remember that radio broadcasting and television were (and in some cases still are) transmitted by tubes, which can deliver full power into the MHz range...something transistors struggle with.
I give up: you are twenty or more years behind the times and refuse to catch up to the present. Wake up Rumplestiltskin: it's 2006.
BTW: will you mind if I quote some of yourposts for my upcoming article?
d.b.
Sorry, couldn't resist :-).
Yes I mind. That means you do NOT have permission so don't use any of my quotes here.
nt
No, just don't want quotes to be taken out of context or to be your pin cushion with no recourse. So don't quote me in your article.
like SPLs even approaching 110 db. I value my hearing far too much.rw
Good for you. It's clear there are others who don't...or at least didn't and made mistakes in their youth which have had consequences they will continue to pay for, for the rest of their lives. In addition to questionable hearing accuity, they displayed poor judgement.When Edgar Vilchur retired from Acoustic Research Corp which he founded, he went into the hearing aid business. I always found this ironic. I wonder how many of his customers for his second line of products acquired the need for them by owning and abusing his first line of products. It seems to me that much of the baby boom generation abused their hearing by attending ear splitting rock concerts and discotheques and are now in various stages of progressive deafness. It was the auditory equavalent of staring straight into the sun. After that you can hardly claim to be a discriminating art critic.
You worry too much. At the AES last month, I met up with one of the Grateful Dead roadies who I worked with, starting 36 years ago. He isn't deaf. He didn't have a hearing aid, but he worked with the Dead on stage, until they broke up about 10 years ago, and he had been working with them since about 1968. Nobody who I know wears a hearing aid. What is this, scare stories? On stage, we pushed bass levels of approximately 130dB.
In 1974, I went to a Chicago concert with a couple of friends. Unfortunately, I was seated fairly close to one of the PA towers. The next day, my left ear was ringing big time. I went to my ENT who said that I likely didn't cause any long term loss, but strongly recommended I avoid that kind of contact. I took his advice.Call me a whimp, but I wear Shure ear buds whenever I fly (my work involves lots of travel) not only to listen to music, but to lower the overall noise level. I wear ear plugs when I mow the lawn. Ear plugs AND headphone type hearing protection when I target shoot.
rw
I agree that you can hurt your ears, AND 'ringing bigtime' after a concert is a good indication that you have been exposed too much. This happened to me in 1970, when I first went to work with the Grateful Dead. Janis Joplin sat in with the Dead, and I was virtually sitting on the loudspeakers that night. It was a warning, but subsequently I was a bit more careful, yet the actual (B&K) soundmeter readings on stage could be 120-130dB of BASS energy, not midrange energy, and it seemed to be OK.
Of course, if I saw that the roadies, musicians, the mixing engineers were now using hearing aids, I would regret my exposure more than I do, but let's be realistic.
How loud can an AR-3 loudspeaker get, when driven by a tubed 60W amplifier? Why don't some of you 'engineers' out there calculate that for me? That was the highest standard advertised by Edgar Villicher when he was with AR.
...in the early 1980s you must have seen J. Peter Moncrieff (a big guy) riding his bicycle around Berkeley in a t-shirt and shorts wearing ear muffs.Quite a site.
Hmmm. Not very? :)rw
"What is this, scare stories? On stage, we pushed bass levels of approximately 130dB."The sound intensity experienced was 24,000 times the acceptable maximum long term exposure OSHA established a long time ago to prevent hearing damage and loss in industrial environments. Do you think with every corporation in America having an army of lawyers ready, willing, and able to fight the government to escape the cost of compliance, OSHA just pulled its number out of thin air? You can dismiss the damage you assisted in inflicting on yourself and others decades ago but no matter how you feel about it, it won't bring anyone's hearing back to what it otherwise would have been. Anyone exposed unprotected to such sound intensity should be grateful just to be able to still hear anything at all.
"What is this, scare stories? On stage, we pushed bass levels of approximately 130dB."And you seriously expect people to seek out, carefully audition, and buy your electronics on the sole recommendation that you say it sounds better after having exposed yourself to this kind of abuse repeatedly and with nothing more concrete to back your claims up?
You who claim to hear the difference between one wire and another, the difference between one capacitor and another, and other differences so small that often the best electronic test equipment in the world can't measure it, now tell me that you can't hear amplifier clipping? I needed a good laugh to start off my day, thanks.
BTW, you call warnings of exposure to 130 db scare tactics? Don't put that on me, read the countless reports and warnings of audiologists and other medical practicioners. They are all over the internet a few mouse clicks away. Anyone who would take your word for it on this one would put a lot more at risk than just money thrown out to buy unnecessarily expensive electroncs. And unlike you...those doctors do have facts and hard data to back them up...lots of it.
I just want to know how I can quiet the gang of Hispanic carpenters working on the house next door. I've got a sound level meter on them right now.
Now that is damaging both to the ear and the psyche.
Sending over a case of Cerveza should do the trick...rather quickly too I'd think. If that isn't enough, try sending a fifth of Tequila with it. If that still doesn't work, have a few yourself. The noise won't stop but you won't mind it half as much.
I should hve mentioned this in the previous post but the 110db/spl is at the loudspeaker!
d.b.
Sound at that level risks permanent loss of hearing due to damage to the fine hairs which transmit sound in the inner ear. Unfortunately, many people have exposed themselves to sound at that level and higher over extended periods. The process is irreversable and there are no known cures. Despite what I've read others post here, the SPL of a 100 piece symphony orchestra playing at full volume (fff) rarely goes over 100 db in the audience.Here is a calculator which will help determine the maximum SPL for a given speaker, available amplifier power, and listening distance.
"Despite what I've read others post here, the SPL of a 100 piece symphony orchestra playing at full volume (fff) rarely goes over 100 db in the audience."I have to disagree with this.... I've heard quite a few unamplified orchestral performances where I thought the peak SPLs approached 110 dB. Note that these are instantaneous- Such as a combination bass drum thwack and cymbal crash.... The levels were not sustained long enough to do major damage to one's hearing.
Also note that a distorted signal will seem louder than a clean signal at comparable SPLs. And because of that, a symphony orchestra rarely sounds "loud", but the acoustic energy that's present is of a higher SPL level than one would think.
z
I never sit ten feet in front of the trumpets. :)rw
I cannot believe it but I am in 100% agreement with Soundmind about the detrimental effects when people listen to their audio systems at loud volume levels at home.I know SET's aren't popular with many folks here but one of the many things that attracted me to SETs was they "sound" correct even at the lower volume levels I typically listen at. In comparison I found most solidstate amps seemed to loss more and more of the emotion of the music as the volume levels decreased.
It's good to know that we at least agree about listening at sane volume levels Soundmind...
Thetubeguy1954
tube boob;
Who are you trying to convince yourself? You are just a habitual liar who's mean-spirited and attacks anything and everything from a person's POV on audio to the physical health. You simply wish to provoke the others, in a vain attempt to provide yourself joy at their expense. You know I no longer take anything you say seriously. HOW CAN I WHEN I'VE CAUGHT YOU LYING SO MANY TIMES? So as you know:1) I don't take you seriously.
2) This will be the ONLY response you'll ever receive from me everytime you respond to any of my posts.I don't understand why you even bother responding to my posts!
Soundmind
Soundmind,You know I posted that I was going to do my very best to ONLY address the topic. I am attempting to be civil to everyone. As much as you berated me for calling others names etc, it was ONLY done after the others had called me names "Tube Boob" etc for an extended time and I got tired of it and decided to treat these people with the same type of behaviour.
If you wish to respond to me like this even when I am in agreement with you, so be it. But I NEVER lied to you. Granted I said, I'd only respond to you with canned copy & paste answers, but I have changed my mind, that is NOT lying. If you wish to continue to call me a liar please at least provide some evidence of WHEN (YOU'VE) CAUGHT (ME) LYING SO MANY TIMES?
But no matter how you choose to continue behaving I agree with you on this subject.
Thetubeguy1954
tube boob;
Who are you trying to convince yourself? You are just a habitual liar who's mean-spirited and attacks anything and everything from a person's POV on audio to the physical health. You simply wish to provoke the others, in a vain attempt to provide yourself joy at their expense. You know I no longer take anything you say seriously. HOW CAN I WHEN I'VE CAUGHT YOU LYING SO MANY TIMES? So as you know:
1) I don't take you seriously.
2) This will be the ONLY response you'll ever receive from me everytime you respond to any of my posts.I don't understand why you even bother responding to my posts!
Soundmind
" I have changed my mind"
I haven't.
Soundmind,It's quite ok with me that you haven't changed your mind. So now it's you who's acting childishly and seeking attention, not me! You are doing the very things you berated me for doing. Talk about a hypocrite? So Be It! However there's one HUGE difference between you & I. When I said HOW CAN I WHEN I'VE CAUGHT YOU LYING SO MANY TIMES? it was because I actually caught you lying, but you haven't caught me lying!
So go ahead and take my post delete your name and add mine. It's just another of your lies I'm sorry to say. So don't worry I won't respond to your posts anymore civily or not. It's quite apparent you don't want me too, I only hope and pray I can expect the same from you as well. If you want me to leave you alone, then you leave me alone. Now that would truly be a relief!
Oh yes I thank you for proving my point that when I acted out childishly or when I called you and the others names, it's was only after 1) you did so to me first (like you're doing here) and 2) I got sick and tired of sitting back and allowing you to. So Bye Bye Soundmind. In this case parting is very sweet.
Thetubeguy1954
tube boob;
Who are you trying to convince yourself? You are just a habitual liar who's mean-spirited and attacks anything and everything from a person's POV on audio to the physical health. You simply wish to provoke the others, in a vain attempt to provide yourself joy at their expense. You know I no longer take anything you say seriously. HOW CAN I WHEN I'VE CAUGHT YOU LYING SO MANY TIMES? So as you know:
1) I don't take you seriously.
2) This will be the ONLY response you'll ever receive from me everytime you respond to any of my posts.
I don't understand why you even bother responding to my posts!Soundmind
I live not too far from Denver, so I went to the RMAF. The only room I visited was this one, to check out their demos. It was pretty interesting and thought-provoking.They had a 35 WPC tube amp designed by Bob Cordell (push-pull, not SET) and a solid-state amp that put out about 240 WPC. There was a handheld switch you could use to switch between the two amps. Levels were matched. I had never done such a test before. I brought in a CD and played the solo piano version of Malachi from Andrew Hill's Time Lines CD. This is a beautifully recorded piece, and one that moves me emotionally very much. Speakers were DIY two-way monitors that appeared to have 8" woofers. These were built by Peter Smith, the main host of the demo. I was amazed at how good these small speakers sounded.
I tried to figure out which amp was which. The first thing I noticed was that I was wishing I had brought a very repetitive piece of music for this test. This would have allowed listening to a section with one amp, then switching, then listening to the repeated sounds with the other amp. As it was, each time I switched I found I had lost my frame of reference because the music itself was rather abstract and ever-changing. I was trying to detect a slightly flabby bass, which I would have attributed to the tube amp with its output transformers. The non-repetitive nature of the music I chose made this very difficult. The second thing I noticed was that my emotional attachment to this piece of music was getting in the way of trying to figure out which component was which. I found myself just wanting to leave the switch in one position and just listen to this great song on a great-sounding system. So I did.
One conclusion I drew from this is that the popular audiophile notion of attributing "involvement" to the properties of a piece of equipment is to me just hooey. For me, the emotional involvement was a big distraction from trying to figure out one piece of equipment from another. This may be particular to me as an individual though. I've often been completely baffled by audiophiles who have what they call "office systems". I wonder how they get any work done while listening. To me, this would be like trying to get work done while having sex. Not gonna happen :-). Bob Dylan said it best when he said "The geometry of innocent flesh on the bone causes Galileo's math book to get thrown".
This demo also got me thinking about some other things. Trying to assess the quality of power amplifiers in normal listening tests with speakers isn't exactly foolproof. Of course speakers produce distortion, and lots of it. Suppose you had a speaker that, when hit with a low-distortion, high-power signal sounds harsh in the midrange and treble on the peaks. Now suppose you had a tube amp with only moderate power, and an overload characteristic that is like a very soft limiter and subjectively less unpleasant than that of the speaker. Combining this amp and speaker might result in the amp preventing the harsh overload aspects of the speaker from acting up. So while the tube amp is less accurate than the high-power solid-state unit, its soft limiting might do a nice job of covering up a somewhat harsh speaker behavior at high SPLs. This is just speculation of course, but it doesn't seem totally far-fetched to me either. Now look at another extreme case. Suppose you have a subwoofer that "takes a licking and keeps on ticking". Powering such a sub with a low-power tube amp will definitely show the deficiencies of the tube amp, while a good quality, high power solid state amp is likely to sound much better in that application.
WHere they showed a typical over compressed pop recording played at a moderate volume. The resulting power consumption was around 2 watts and hardly moving at all (thanks compression!). Next they put on a well recorded opera that had an explosion of some kind. THe PEAK power was around 2000 watts!!! However; when watching the power needle through most of the performance the power was well below 1 watt and often around 1/10th of a watt. We also tried a good recording of Mahler 3rd symphony. This one hit well over 500 watts on some big drum hits but most of the time hovered between 0.1 and 10 watts.The point the demo thought it was making is that you need an extremely high powered amp to cope with huge dynamic demands. However; as they showed most music doesn't have much contrast in dynamics so actually not much power is needed. Also, the average power on the acoustic recording was very low, usually 1 watt or less and the peak that hit 2000 watts lasted maybe a few milliseconds at most.
The point this really makes, at least to me is this: At the peak of extreme dynamic recordings nearly EVERY amp, SS or tube will clip. Likewise, for dynamic range restricted recordings (nearly all pop) the amp is likely NEVER clipping...even modest power on lower sensitivity speakers will play pop clean at plenty loud levels (over 90db).
The question then becomes HOW does the amp clip. If the amp clips on the peak but then as soon as the peak has passed goes on its merry way as if nothing ever happened then there is a very high probability that you will never even hear the clipping. If, on the other hand, the amp feeds that clipped signal back into the input thus inducing further clipping and distortion or worse, the amp oscillates, then the sound of clipping can be painfully obvious. Most high power amps , when they clip do so very abruptly and in a hard way. They tend to recover quite slowly from this clipping.
"Most high power amps , when they clip do so very abruptly and in a hard way. They tend to recover quite slowly from this clipping."I don't agree. Recovery speed can be related to the size of the power transformer and how well regulated the power supply is. If the B+ voltage is pulled down by excessive current draw, the Transformer could get it back to nominal in 1/4 to 3/4 cycles if the capacitors aren't too big for it. Large capacitors will take longer to recharge. Well designed solid state amplifiers can recover from clipping very quickly. BTW, the clipping point of vacuum tubes can vary considerably with the temperature of the cathode which is related to the square of the current. That's why changes in utility voltage can have such a large effect on them. That also changes the quiescent operating points of all of the active devices if the supply isn't regulated and the amplifier is even more sensitive to it if there is not negative feedback in the signal path. I'd say the main electrical characteristic of the zero feedback SET is drift. Small wonder people never turn them off hoping they will stabalize. Only problem with that is besides heating the room up is that it shortens the life of the tubes. We've come a long way since those days. Well some of us have anyway.
A bigger issue with clipping is negative feedback. Why do you think most SS amps have such a hard clipping behavior?? That clipped signal is fed back into the input thus reinforcing the behavior. No feedback amps do clip less aggressively and when the transient has passed so has the problem. Feedback keeps the problem a problem for more cycles.
Feedback or not.
Stick to chemistry;
d.b.
depends on how long it stays clipped if it is audible or not. I would tell you to stick with what your good at but I am not sure what that would be.
It has long been known that clipping at low frequencies is much harder to hear than high frequencies, obviously due to the incredible distortion woofers generally present at high excursions. Your obsession with negative feedback is duly noted, however, audio amps are judged by what they do in linear mode, not when they are clipping.
Do you know the difference? I wonder.
Stick to chemistry;
d.b.
"It has long been known that clipping at low frequencies is much harder to hear than high frequencies"So what? Most of us would be concerned with the high frequency garbage coming out since it IS much more audible. Why even bring this up??
"Your obsession with negative feedback is duly noted, however, audio amps are judged by what they do in linear mode, not when they are clipping"
Maybe that's how amps are judged but the topic is about clipping is it not? Try to stay on subject, I know its hard for you when you have nothing meaningful to say but try anyway.
And how are most high feedback amps judged in terms of sound quality when operating in the "linear" mode? At what frequencies? As I have shown with measurements, many high feedback amps show a marked increase in distortion as a function of frequency. Clearly they get much less linear at higher frequencies. Also, what do the harmonics of that distortion look like? THat is more important anyway. Do you think this gets better when the amp clips? More likely it follows the tendency and makes even MORE high frequency high harmonics when it clips.
When all amps clip there is for sure a whole spectrum of high order and high level distortion products. This is clear and in severe cases clearly audible. What I want to know is with a high level burst that pushes an amp into clipping how quickly does that amp return to normal operation once the transient has passed? Can you tell me this for your amp? How many microseconds? Milliseconds? Seconds???? Does your amp have a little wobble (ie. does it oscillate a bit?)? How does this compare among amp circuits?
IMO, most pop/rock listeners will not clip their 100 watt amps. You and I both know that this genre of music is so compressed that a few watts will be plenty loud with most speakers. YET, most amps still sound different from each other. So clearly distortion is not below audible thresholds or even at the limits of hearing.
For non-compressed acoustic music the average levels will be much lower than the compressed rock music and therefore the demand for power will usually be much less than for the rock (so we are talking quite low powers here). The PEAKS will likely drive many amps to clip (I saw a demo that showed up to 2000 watts on a music peak where average was below 1 watt) so it is not a question of if but when.
For example you have a 45 watt tube amp and 300 watt SS amp. Now for most of the music the demand at a reasonable listening level is between 0.1 and 10 watts but peaks go to 500 watts. Both amps clip but only on the same peaks, at all other times they are both operating in "linear" mode. The question then becomes: Is the clipping audible from both amps? If so, which one sounds worse at clipping? The big 300 watt amp will hard clip, being driven about 3db over its limits, how fast will it recover? The 45 watt amp will also hard clip, being driven about 10db over its limits, how fast will it recover? I am speculating that the 45 watt amp, having no feedback, will recover more quickly. Why? Because if the SS amp has high amounts feedback then a substantial clipped signal is fed back to the input and may make the amp continue to clip (or oscillate) long after the transient is gone. Can you prove to me one way or the other is correct? This has been noted by other designers so it is not like it should be something new to you.
Honestly, you are so biased in favor of your own technology that you can't even think about the problem logically. You just try to bash me which simply shows me you don't know because you never tested your amp for clipping recovery, did you? Your amp will for sure clip on some peaks because it is not all that powerful, am I right?
I've already tested my amp for clipping recovery, see Soundminds posts on supply regulation vs. recovery. I gotta hand it to you Brad, no matter how stupid your ideas are you just keep flailing away. A for effort, F for content.
Stick to Chemistry;
d.b.
"see Soundminds posts on supply regulation vs. recovery"
and where might those be? I am not going to search through Soundmind's thousands of posts. Either that or post the data again, it is for sure not that much.Don't redirect me, tell me the numbers. Until then I assume you are full of it. Next time get someone who knows how to read a schematic to proof read your designs.
My recent experiments with a speaker requiring substantial bass boost to equalize its output making the deepest bass it is capable of flat has convinced me that clipping is a horrible sound. The distinction between so called soft clipping where the peaks are first compressed before they simply don't result in any further increase in output seems to me a false one as harmonic distortion will rise rapidly in either case when the amplifier is pushed into overload. Therefore a nominally rated 60 wpc tube amplifier shouldn't be expected to perform any better than a 200 wpc solid state amplifier whose distortion versus power output curve rises more steeply. It's that curve which defines the usable limits of the amplifier in real use, not the nominal wattage rating, the desire by consumers for simplified numbers to replace more complicated notions notwithstanding. Therefore the idea that because one type of amplifier clips with predominantly even order harmonics while another clipps with odd order harmonics seems meaningless. One very important characteristic is the speed with which an amplifier recovers from overload and this is usually a measure of the conservativeness of its power supply. The faster the recovery, the less audible an event but this demonstrates how important it is to "engineer" a sound system rather than throw one together like a tossed salad picking individual components on their own without any thought to how they will work together. The low powered SET, an exceptionally poor value on today's market, is unsuitable for use with the overwhelming majority of loudspeakers playing most kinds of music under most circumstances. Their viable only use is relegated to the most efficient speakers available.The measurement of actual power output is far more complicated than simply measuring the voltage and assuming the speaker is 8 ohms or 4 ohms. A impedence versus frequency plot will show that the impedence for most speakers varies all over the place while a pole zero diagram will show it's phase angle does too. Therefore, to know how much actual power is delivered to the load, a meter would have to measure the voltage, the current, and the phase angle and compute the result by the well known formula P=V*I*cos theta. Will the meter in the article do this? A slightly less accurate measure is the VAR or Volt-Amp-reactive product which omits the phase angle. This can be useful in determining if transformers have been overloaded since they are often specified that way. The proof that the so called power meters on amplifiers are useless can be easily demonstrated by disconnecting the speaker. The meters will swing back and forth just as they normally do even with the actual power output at zero. People do like to look at them anyway.
Here I've been listening to nothing but distortion and clipping -- for years! -- and loving the sound. 12 wpc SET tube monoblocks via medium sensitivity speakers (Gallo Ref 3s) in a really BIG room and my friends and I thought wrongly that it sounded wonderful. Of course they're all listening to tube amps as well -- 2.5w, 6w, 12w (same amps as mine), 18w, 24w -- so their hearing is clearly deficient too, and I don't remember ever hearing one of their systems clip. How embarrassing!
.
.
.
Mark,I don't know about you but I'm amazed by how many of the Objectivist crowd here always wants to bring the topic back to Subjectivists and how they are somehow to blame for almost anything! I'm beginning to believe these Objectivists would really prefer arguing than actually discussing the topics they've raised.
For Example: I've noticed since I've stopped arguing with AJinFLA he either ignores the questions I ask him, or if he actually does reply it's with replies like "Do you use my posts when you shave? Rather than seeing the words I have typed on a computer screen you seem to be seeing a reflection of one's self. A rather strange occurrence IMHO. I wonder if your hearing and vision are of that ilk." meant to provoke me rather than intelligently response to my questions & statements of mine in this response: http://www.audioasylum.com/forums/prophead/messages/25068.html
Or you can take Unsoundmind's reply when you stated "The topic of Dave's post was clipping and distortion in flea-powered amps, not hearing loss." Unsoundmind's reply was "That's the problem with discussing audio over the internet with subjectivists. You have no way to know who can actually hear anything and who just parrots back what other people have said to him." as if that is somehow an intelligent respond to what you've said.
I've decided to join my fellow Subjectivists and not take the Objectivists bait anymore. As I posted before for me the Subjectivists vs Objectivists battle is over. You cannot possibly discuss or debate, let alone try and win a debate, with people who won't respond to your questions, but instead prefer saying anything they can about how it's the Subjectivists who are to blame for whatever a given problem is.
Thetubeguy1954
That's the problem with discussing audio over the internet with subjectivists. You have no way to know who can actually hear anything and who just parrots back what other people have said to him.
We have no idea if you actually understand anything or are just parrotting things back that you read somewhere.
I'd take offense, but considering the source that would be rather pointless.
.
AJinFLA,As I said I'll try to address the subject mentioned when responding to posts.
I'm noticing a continuance of the very childish trend of yours to need to berate & insult those who disagree with your POV. This childish and unbecoming behaviour is portrayed in your statement "This might be an interesting article for those who are not interested in the Belt type "interesting" articles, i.e., the non-voodooist, non-knot-tying, non-fluoride sniffing type..." The obvious implication is those who find the Belt type of articles "interesting" are thus the voodooist, knot-tying, fluoride sniffing type of music lovers. It would be quite interesting to see if you're capable of talking or debating a topic without having to always insult those who disagree with your POV. For example it would have been just as easy, actually easier as it would require less typing, to have said... This might be an interesting article for those who are not interested in the Belt type articles. See it can be done AJinFLA.
You are making a few of assumptions when you ask the question "I wonder if there is anyone naive enough to use a low powered tube amp with low to medium efficiency speakers and yet vehemently deny craving distortion?"
1) The distortion is audible.
2) It's heard and noticably recognized as distortion.
3) One must be naive to believe differently than your POV.Before making such a statement YOU would actually need to provide proof that the distortion is indeed audible and it's heard and noticably recognized as distortion. Otherwise how can you claim these people are craving distortion? Perhaps they don't hear or recognize what they are hearing as distortion! IMHO unless and until you are willing to prove via your beloved DBT's test with an ABX comparator that YOU can personally identify EVERYTIME when a low powered tube amp with low to medium efficiency speakers is #1) distorting and #2) you can always identify when it's heard and recognize it is distorting, ONLY then can you honestly claim that you know the distortion is both heard and recognized as distortion and thus anyone who uses such a setup is possibly craving distortion! However the fact is the ONLY thing you will have actually proved is you can detect and recognize the distortion.
So AJinFLA I'd suggest you actually try providing PROOF that those who are using a low powered tube amp with low to medium efficiency speakers are in fact able to hear the distortion and recognize it is distortion, it is very naive on your part to assume and claim that anyone who uses such a setup is possibly craving distortion!
Thetubeguy1954
Rather than seeing the words I have typed on a computer screen you seem to be seeing a reflection of one's self. A rather strange occurrence IMHO.
I wonder if your hearing and vision are of that ilk.cheers,
AJ
The threshold for disproving something is higher than the threshold for saying it, which is a recipe for the accumulation of bullshit - Softky
I have noticed you seem unable or unwilling to hold an intelligent debate or even defend your postion when it's challenged. You made what I find to be a quite absurd and unsubstantiated claim in a public forum. I chose to address the parts I considered to be both absurd & unsubstantiated about your claim. It's appears a few others agree your statement was flawed as well I thought you'd like to defend your POV.So why not try addressing the questions I posed? That is "If" you honestly believe what you posted, i.e. "I wonder if there is anyone naive enough to use a low powered tube amp with low to medium efficiency speakers and yet vehemently deny craving distortion?" Or were your comments simply intended as a slap at those who use powered tube amp with low to medium efficiency speakers, because it's a differeing technology than what you prefer? So giving you the benefit of the doubt and assuming you honestly believe your question is a valid one, I'll ask once again AJinFLA can you prove 1) The distortion is audible, 2) It's heard and noticably recognized as distortion & 3) One must be naive to believe differently than your POV?
Are you going to choose to respond childishly to my intelligently & civily asked questions by refering to me as a voodooist, knot-tying, fluoride sniffing type simply because I prefer different audio tecnologies than you? Or are you going to answer once again with another absurd comment like "Rather than seeing the words I have typed on a computer screen you seem to be seeing a reflection of one's self. A rather strange occurrence IMHO. I wonder if your hearing and vision are of that ilk." as opposed to actually defending your postion?" That response makes absolutely no sense to me, considering the questions I asked!
If there is ANY strange occurances happening here it's how you choose to respond to the intelligent and civil replies your provocative questions receive. I'm starting to believe that you really do prefer provoking others into arguements rather than intelligently discuss or debate anything if those who respond have opinions that different than your own.
Thetubeguy1954
Hi.I agee what you commented word by word. Why waste time on someone who chooses to behave so "childish" & "absurd".
c-J
Most of us realize that most real hi fi information is there in the first WATT. After that, it is just musical peaks or sound effects. It is interesting that 0Vu on a tape recorder originally meant that the tape added 1% distortion, that then doubled for every 3dB increase in level. Therefore a 6dB increase gave 4% distortion, and a 12dB increase gave 16% distortion. How can we live with this, yet call it high fidelity? Well, the best recordings of the 50's and '60's followed this rule, yet can sound just fine, if not a 'little' compressed. The most important thing is that the distortion is smooth and well defined. IF the record amplifier actually overloaded, itself, and added higher order harmonics, or latched up momentarily, we can hear it easily. This is why we have to make analog record electronics that doesn't easily overload. Moreover, momentary overload of a smooth kind, usually caused by low feedback electronics is not easily heard.
nt
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