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Subjective review of audio equipment is the workable way to evaluate what we are hearing but these DBT guys don't believe anything they hear. How do they put together a system and what do their systems sound like? If all amps sound the same how do they pick 'em? Price per pound?
I thought maybe "DB" stood for decibels. In the current issue of StereoPile (and yes, I now view it as a pile of dog excrement with occasional worthwhile reading) some oaf tries to match a new release Classe digital switching amp to a twenty year old Proceed linear amp by matching decibel levels as if that somehow places both on equal footing for all further subjective comparisons and contrasts. It's analogous to thinking that racing a 2017 Maseratti against a 1997 Buick Skylark is instructive as a race of two comparable vehicles as long as you start them even to the line. It assumes that all that matters for valid comparisons is loudness. Yes, we all get it; that loudness should be matched but who the hell cares about how some just released component compares to a mid-fi relic? Oh well. Carry on.
Go outside, get some fresh air. :)
DBT has its uses, but listening to music on hifi systems isn't one of them.
Sighted testing, on the other hand, can readily expose listener bias.
Testing and listening to a produced recording are two different mental processes, and as Tom Servo mentioned - Live listening is a completely different "Third" process - the most natural one. Real signal Real Time - only perception (not that those producers might not try to fool us.)
I digress, Of source you can test the signal with instrumentation to amazing precision these days. You can compare any signal input to a device to its output and overlay the traces to 24bit or higher precision. Of course you have to make the argument that the XXXkHz Sampling rate and NN MegaOhm input impedance and the connecting cables are not effecting the tested system network response.
If you go and try to analyze the signal (Frequency Analysis, for example) you have to recognize the parameters of the analysis set limits to the assessment. Many times the Analysis gear for audio is not that flexible - Swept sine testing is used or a random or pseudo-random signal. If you use an FFT Analysis - you capture the signal in blocks - and often the user or system sets his goals for high levels of frequency resolution with averages long blocks of information. For audio testing for human perception - where our time discrimination is pretty good - you'd like to keep the FFT block size down to 10msec or so which means a relatively poor 100Hz resolution. That's a 200 line analyzer with a 20kHz span.
Our (Bruel & Kjaer) can be set up to measure with a very wide dynamic range and with completely flexible analysis parameters all in parallel. And you can set up virtually unlimited "tap" points as we can synchronize the measurements inputs across 100's of channels. I have absolute confidence that we can detect the differences in a signal at any analog point on a system.
Of course, another way to test is to listen with your ears. Blind testing is a proven way to establish preferences - and with experience you lose the "pressure" of making a choice. And it is important to not know what you are listening to. Whether you expand that to a DBT is another issue.
The brain is working differently when in the "test" listening mode - than when in the "listen" listening mode. a
Audiophiles Listen to recordings for different purposes. To simulate a live event is one of those. or it could be to enjoy the artistry and technique of the musician, or it could be to see how their system throws and image, or how the recording produce decides to present the image. Or is could be just to sit and relax and meditate. Often with me, as with others, we do all of these...
The important thing to remember in all of these - there is the factor that the event we are experiencing while listening is as much imagined as it is real - perhaps even more imagined than real. In this imagined environment it is completely possible that you can have two identical signals and get two different experiences. Changing a power cord for in instance may or may not change the signal (I have never measured a change in a signal due to a power cord change in my lab or listening room) but it certainly can change the experience. This was one of the characterstics represented in Heyser's "Catastrophe Effect" as the manifold of our listening "plane" is constantly changing by our other observations happening before or during the experience.
I'm a test engineer, but as a hobbyist in audio, I embrace the subjective part of the experience - it is what makes the hobby great. And perhaps why other hobbies that effect the senses - Cigars, wine, beer, cooking, art, and music, and I'm sure many others have passionate participants.
AA members - if anything are passionate participants.
"The hardest thing of all is to find a black cat in a dark room, especially if there is no cat" - Confucius
The problem is our live conscious audio experience is made up of inputs from your two ears and your eyes and what you have experienced in your life, all these make up our audio experience and it's processed in your head without your awareness..
The problem with comparing two things without knowing which one your hearing is this reduces the entire process to only what you can hear with your two ears.
Proponents say well if you can't hear the difference why pay more etc, critics say this isn't anything like what one experiences when listening normally.
Which is right? both in a way but if one is engineering products other people will use with different choices of music, then the blind tests which show one better than another should not be ignored.
The flaws in audio equipment, especially loudspeakers can be heard very easily in a generation loss test, these do not tell you what to fix, but by hearing the problem more clearly, it often points the direction.
While modern electronics can pass several generations without being objectionable, loudspeakers rarely go past 2 generations.
a few day ago was PI day 3.1415... the first the non-unity numbers:
3-4-5 form the first Pythagorean Triple - order 1. Order one because it is the radius of the inscribed circle of the 3-4-5 triangle. Conveniently it is also twice it's area divided by its perimeter. In fact, the inscribed circle of all triangles formed by Pythagorean Triples have an integer radius. Life is good!
"The hardest thing of all is to find a black cat in a dark room, especially if there is no cat" - Confucius
It's easier to tell the difference between different brands of peanut butter than audio equipment?
....swap that Audionote amp for a Yamaha receiver and put some coin in your pocket.
Don't worry about avoiding temptation. As you grow older, it will avoid you.
- Winston Churchill
I made a thread on another website and it was very revealing for me. All the hard core DBTers are convinced that DBTing is the only way to test equipment AND most believe that all amps, pre-amps, cables, and CD players sound the same. I was unaware of the depth of that conviction. BUT, the surprising thing was that nobody does ANY DBTing to evaluate their own equipment in their own home. They all accept that there is no purpose to testing in the home because they already know the results without testing. Well there goes the scientific approach, lol.
But they don't need to do a DBT - reading about how others did and or tests run by corporations who sell the product being tested is all the evidence that is required. Seriously, a corporation would never mislead the public in any way about their products.
The corporation always has your best interest in mind.
The DBT guys use testing the way politicians use the truth. The truth is SO important that they only use it when absolutely necessary.
P.S. I might have a quotable quote there, lol.
is where we go with repeated comparisons and the momentary aversion to being wrong. fatigue under those conditions is what prevents dbt from success.
long term listening adds up data within the brain and is able to discern fine differences without the need to make a snap decision.
we don't all have the resources of harman international to properly carry out dbt.
...DBTs can be useful in product development or research.
I don't find them much more than a parlor trick at home.
Every successful equipment designer I know of fine-tunes his finished product by ear.
The idea that most all amps sound the same is ridiculous when you think about the different designs, topology, parts quality, etc. and the different loads they are driving.
Back when I was reviewing, I heard 3 identical amplifiers (Adcom 535s) that all sounded different - it turned out they were all biased differently. The best sounding one was biased correctly.
"we don't all have the resources of harman international to properly carry out dbt."
Nor should anyone trust the results of a corporation that conducts tests and sells the product they are testing.
This is called a "Conflict of Interest."
Harman's products fly in the face of that remark. i don't think that dbt is without value, just that it isn't a requirement for owning or not owning a product.
when it is used as a pissing contest, then it is a waste of time. also, those that march ONLY to that beat are like mice or sheep. it's like those that live by test result numbers alone.
the lesson was learned with the advent of solid state electronics and many sold off their tubed components and when were left holding the bag with systems that didn't sound good and natural.
That was the first lesson I learned in hi-fi. Sold off a very nice five year old Fisher 500 (tubed) receiver that I bought new from the dealer and bought one of those horrible AR integrated SS amps because I read Julian Hirsch's review in Stereo Review and believed it. Got rid of that POS in less than one month. That was a very long time ago (about 1966) and an expensive lesson for this young kid to learn.
Some of these "Reviewers" are full of it and are either liars, tone deaf or on the take. I'll forever be in debt to Julian Hirsch for teaching me a valuable lesson. I wish that I would have been able to "thank" Mr Hirsch before he died. Now all that's left would be to piss on his grave (if I could find it).
...and bought one of those horrible AR integrated SS amps because I read Julian Hirsch's review in Stereo Review and believed it.
I did that when I was 15 and didn't have a clue. It didn't take long to determine that the amp worked great at high power, but resolution tanked at low levels. I kept mine for a bit longer than you.
I did, however, get a glowing THD chart from none other than Dave O'Brien at a local McIntosh clinic.
That experience demonstrated to me the irrelevancy of the THD metric. :)
i have to give him SOME credit because he got me to reading audio mags and understanding what distortion is an some of what to listen for.
i once referenced him to another enthusiast and was laughed at which stared me looking for another source besides high fidelity and stereo review. THEN i discovered AUDIO Magazine where things were more real.
later on, a friend turned me on to tas and much later stereophile, both in small format. i wallowed in those and still do to this day.
back to julian. he reviewed the JBL L100 which was a great looker with its waffle grille in numerous covers. they advertised in every conceivable magazine.
the upshot of his review was like this-the L100 is uncommonly flat from 30cps to 16k cps. well.....NOT. he had by then lost all credibility with me. i still subscribed to Stereo Review because the tariff was the lowest and it was at the least worth paging through.
its descendant is Sound and Vision which does the same thing but to be fair, sometimes has good reviews and reliable graphs.
another reason i didn't want to relinquish the subscription is Strve Simels, whose music reiviews pulled no punches. if he said it was good, you could bank on it. if it was crap, he was very plain in his use of the language. unusual for a critic in a mass market publication.
j godron holt was fired from high fidelity mag because he did the same with equipment. the infinity servo statik fared VERY well in contrast.
comes from an engineer over at vintage:
He's not on the take...
somewhere along the way. Before HH Labs, he published the Audio League Report. There are a few issues floating around the web. His reviews were very subjective, and he frequently printed negative reviews due to awful sonics. HH labs handled reviews for High Fidelity, Stereo Review, Electronics World and a few others....essentially every mainstream audio/hobbyist magazine except Audio. Good reviews sold ads and kept him employed. I did read somewhere that there were more than a few reviews that did not see print because the equipment either did not work, or sounded so bad that it was just about impossible to spin into positive copy.
There is no good reason to evaluate and review something that sounds bad.
If I'm interested in an XYZ amp, and three different reviewers say they couldn't get it to sound good in their systems, or that it sounded great, but caught fire, then the negative review has done me a great service.
that was BOLD of Jerry to relate that.
Audio was the best Audio publication bar non , sadly missed .......
i loved being able to read bert whyte (one of the stereo pioneers), ed canby , cordesman, and bascom king's amp tests with square wave response REALLY helped me understand audio in general, amps in particular.
the october BIBLE was a welcome issue as well as full coverage of professor I lirpA and his products, costly as they were.
I notice that you didn't mention Len Feldman.
len wasn't my favorite reviewer. sort of a milktoast that didn't get the emerging picture in the hifi press. sort of a les bothersome julian.
FYI, It's Milquetoast. The name of a timid character in an old comic strip.
I learned the same lesson the same way. Now the DBT guys say if you heard a difference then it wasn't gain matched...oh please give up on that one....
If there is no other way to judge two amps. I would certainly buy the much heavier one.
So price per pound works, when all other criteria are excluded.
In the aircraft industry, light weight is king and it costs a whole lot more money?
......... the next time I'm in the market for a flying amplifier ;-)
Somebody in the audio field once said that if there were two ashtrays the smoker would always pick up the heavier one thinking the extra weight was a sign of quality. In aircraft the exact opposite is true. After 30 years in aircraft component design, I further appreciate well designed light structures. After I move my 100 pound amp, my back appreciates light components even more.
switchers are taking over. And they don't have to employ carbon fiber enclosures to be lightweight.
Not the biggest fan of them (although I use a Crown in the garage system), but they are simply more efficient.
"switchers are taking over."
Unfortunately, so far being light and running cool is their best feature. I'm sure better sounding ones are getting nearer.
My Berning ZH270 uses a very complicated switching power supply and being an OTL has no large output transformer. It is a stereo amp and weighs 10 lbs. My previous hurricane monoblocks wer 60lbs each. The Berning is a much better sounding amp.
In today's world of lightweight switchers, price-per-watt might be more useful.
I convinced that either:
1. They really don't have the hearing acuity to tell any difference.
2. They convince themselves seemingly with the best of intentions based upon flawed assumptions. Even when validating (actually refuting) the test methodology can be achieved quite easily.
Click here to read my favorite *test* for comparing interconnects. Scroll down for the section on them. The assumption here is that by using a Y-adapter, one is able to compare two cables using the same source device. Clearly, the author never tested his assumption set. I did and posted my results several years ago. I had taken pictures of my capacitance meter for each step, but deleted those pics afterwards.
Results? The test is a self fulfilling prophecy since there is (electrically) no comparison made at all. There's a link within my link that provides a speaker cable comparison suggested by an inmate with another easily debunked assumption set.
A couple years later, I made that observation over at Planar and got an equally hilarious response. This inmate opined:
"The capacitance is not significant IF the driving source is not affected by it. "
Here we combine both unsupported assumptions AND circular reasoning . So, if one assumes that the cables make no difference, then the test that combines the electrical properties of both as measured at either end might be valid!
Just boggles the mind how some folks reason. :)
What I have learned is that you can make your case for what you think and then let it be. The way they choose to buy gear should not drive you crazy.
Frankly I am a but envious of those folks because when I listen to my four amplifiers I wish to the spaghetti monster in the sky that my cheapest amplifier was just as good as my most expensive amplifier - or ditto that of the 10 CD playing devices I have owned over the years that my discman was indeed just as good with CD replay as all others. I'd save a boatload of cash.
Both sides think the other side is deluding themselves and both sides think they're right. But there is a sense of satisfaction (a bias) when spending $300 on amplifier or CD player and truly believing that it's just as good as something someone else stupidly paid $30,000 for. They get to feel righteously superior and "smarter than you" and that dopamine rush is powerful. They won't be convinced to "trust their ears"
Conversely, the subjective listener loves this hobby and want to feel like they have special super powers and can hear things "average people" can't hear. So they always hear differences in everything no matter what never admitting any infallibility. The brain is geared to solve problems to avoid falling into a feedback loop. Which is why when you look at a cloud your brain references past images and you see a tiger or dragon in the cloud. Problem solved and it can now move on.
In a DBT - when the problem becomes difficult your brain will just make a choice whether there is one to be made or not. I've never liked such choice making tests because this was not what the DBT was designed for and the field of psychology addresses these problems. But you can discuss this issue only so many times and you will get nowhere with them. So don't bother. Let them feel good about themselves and buy what they want. And if they think you're crazy for liking a tube amp over a SS amp or speaker that measures poorly versus their speakers that look great on the graphs that's fine too.
Don't be afraid of the blind test - the goal after all is to not trick you into paying a lot more for something that is sonically no better. And remember MANY brands - in fact virtually all of them are only buying parts from OEM makers sticking the parts in a container and putting their own fancy label on the front. And then they charge for marketing appeal and creating brand prestige when the actual amp or cd player or even speaker is really no better or different than something else.
Theta Data did this - they purchased a Philips Laser Disc player for $300 and they put the ENTIRE machine in their own cheap sheet metal and added ONE $20 part - an SPDIF output and then charged 10 times the money. Then just find some weak minded gullible reviewers to help screw over the gullible buyers who read the magazines.
So I have a bit of respect for the objectivists because for every Theta that gets caught there are probably another 20 that don't.
This is the main reason to not chuck out the objective approach. Not everything sounds different - in fact a lot of what is out there may be almost exactly the same and a very minor difference doesn't justify paying 20 times the price. Pay attention to the design and what is inside the product.
You say, "In a DBT - when the problem becomes difficult your brain will just make a choice whether there is one to be made or not."
Well, your brain is likely to make a choice when there is no audible difference whether you do a blind test or not.
That is a major reason for controlled blind tests.
"A fool and his money are soon parted." --- Thomas Tusser
A very concise analysis, thanx. One question: Did a DBT find the Phillips in the box or not?
No if you read the link I posted - the fellow was in the business of modifying (adding tubes) various pieces of gear - and he took it apart and found that Theta just put a whole machine inside their own.
Review publications raved about this player (and likely never looked inside) because they say stuff like - "based on a Philips LD machine"
Based on and having an entire machine put inside (the Philips case and all) is not "based on."
It would have been nice in the Theta's case for the reviewer to go out and buy the Philips machine and compare them sighted and blind given that Theta's contribution to this is about $5 and cheap sheet metal.
As Fikus noted - he felt that Theta's contribution if anything made the sound WORSE.
"How do they put together a system.......................?"
They just follow what Arny Kruger tells them to do. ;-)
It must be hard to get a significantly large enough sample size to confirm their DBT results. I'm thinking they couldn't get 3 guys to come to their house on a Saturday morning to go through a test session. I guess on the other hand they only have to test music sources and loudspeakers because all cables and amps sound the same? That sure would cut down my workload.
on a dollars per pound basis. Seems as viable as listening in an unfamiliar dealer's system and taking the leap of faith, IMHO.
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