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In Reply to: RE: This are honest questions............... posted by jrlaudio on November 03, 2012 at 03:39:19
elsewhere where George Cardas told me that the predilection for precious metal plating on audiophile ends is bad because the metal galls upon insertion, and that since gold in particular is soft, the affected metal eventually flatten out under pressure. Have you experimented with measuring such an effect?
Figures you mention, particularly in volume changes, are indeed well known, but aren't all the numbers you mention an average? If you take a typical bell curve there will be individuals which fall way out of the specific numbers mentioned. Has any one done research to measure the spread?
The 1.5 dB volume change is the step used in CJ preamps ( I own one), but I often crave for a volume change between steps.
After all, we can say the average human male is say 5' 10" tall, but there are dwarfs and midgets and then we have NBA basketball players.... The spread is quite large, and so can the range of human sensitivities. Do we design for the mediocre or average Joe or do we measure to fit the super sensitive?
Not attempting to put you on the spot or anything, but this is an issue which has dogged me for many years, decades actually. One acquaintance can hear the supersonic pitch used in alarm systems in stores and it drives him crazy (what is it? something like 19kHZ, I can't hear it).
I am sensitive to phase shift although speaker phase shifts are far greater than the numbers you quote. Still I can hear phase in a few seconds, when most of my buddies have to do an AB several times before they can perceive what I hear. Its not always a blessing and can be sometimes a curse.
Still when it comes to something subjective as music is, then perhaps you hit the nail on the head. Of what use are measurements?
I like spicy chili pepper hot foods. My friend's wife absolutely hates it: what to me can be exceedingly bland, she finds fiery hot. Who's to say who is right? At this point it is simply human individuality and no one is correct.
In returning to audio, of what use are measurements? In the same vein, one can prefer seating way back in the balcony of a concert hall and some one else may prefer up front center seats. Same identical performance, but vastly different presentations. Again, there is NO right or wrong, it is simply a preference.
Thus any attempt for me to judge all audio by the simplicity of making measurements of the parameters as we understand them, is essentially useless. You would think if perfect phase, frequency response, and time coherence were the end to all, then all speakers after a certain price point should sound alike. They don't, however, just like you can go to an Italian five star restaurant, or French one, or a Japanese one and each may be equally priced but have vastly different tasting food. A hospital can be antiseptically clean, but I enjoy the pigsty which is my home (Or so the women who have entered term it).
Measurements while a guide, does NOT factor in human subjectivity.
Of course YMMV
Stu
Follow Ups:
Please understand, I am over-simplifying my explanations. I could get very technical but that is not important for the discussion here and would easily bar those less technical from joining in. My hope is those interested enough will do some personal research, away from audiophile blogs, advertising, and magazines. I hope they instead delve into the reams of knowledge contained in papers prepared by academia in this field.While I personally haven't directly measured the affects of plating what I can say is from what I have gleened from others research. The primary reason for their use is the fact that precious metals do not oxidize easily. Oxides increase resistance, and cause intermittent connections. Otherwise, the only difference between precious metals electrically is conductivity. And the differences in conductivity between gold, silver, and nickel are so low as to be non-audible in most applications for connectors. Again, its the lower oxidation potential and improved reliability that brought about precious metals being used on connectors. The alleged audible differences are techno-babble trained into the brains of audiophiles by companies over many many years, successfully trying to increase perceived value and therefore raise prices.
Another more important issue is the fact that plated connectors may in fact be worse than a single metal. For a gold connector to be perfectly consistant and reliable it needs to be solid. The point where the plating meets the underlying metal substrate is a joint of disimilar metals, both of which exhibit different conductivity values. At that junction you in effect have a semiconductor. Also due to the electrostatic differences you have a junction that may be susceptible to electrolysis causing corrosion at the junction, underneath the plating. A solid silver connector, or even solid nickel, is most likely better than a gold plated copper one for these reasons. All this comes from an engineers understanding of metalurgy and electro-chemistry, however I have no first hand test data to support this theory.
The problem I have is I have seen numerous manufacturers make the false and deceptive argument that the cost saving approach of using plated connectors instead of solid is actually attributable to "skin effect". This is a bold faced lie. They claim because of skin effect gold only has to be on the outside of the connector. As I said before skin effect does not occur at or even near audio frequencies. These are physical constants that cannot be disputed. It is a tested, measured and well understood fact. The lowest grade wire does not show skin effects until about 65kHz. And purest wires made of gold or platimum exhibit the same properties in this respect. And since audio is passed equally throughout the entire structure of any wire at the same speed over the entire audio spectrum (as a factor of velocity), the differences between stranded wire and solid of the same gauge in regards to passing signal are identical at audio frequencies. In fact, a solid wire puts slightly more metal in the same volume of space, since a stranded wire has air between all the conductors. Also stranded wire has a minutely higher capacitance, but again to low to have an audible affect. However, the primary advantage of stranded wire is flexibility.
Cardas ... hmm ... Cardas. Mrytlewood blocks. Wood is used in musical instruments because it transfers acoustical energy very well, and it resonates nicely. Why would we then use it to "isolate" gear. I haven't a clue. Cardas does though. And besides, if equipment is so susceptible to micro-phonics as to be audible, there is something seriously wrong with the design. That is a serious design flaw and completely avoidable (with the exception of vacuum tubes proper). But CD players and DAC's. Nope ... sorry. Not real. But it is perceived to be true ... hmm. I'll accept Walkers HDL concept as something real though. A zobel network designed to remove RF from a signal to reduce intermodulation artifacts is certainly something real and quantifiable ... and measurable.
The CJ knob calibrations are of low level electrical signal either dBu or dBv, not dB SPL. These are two totally different things that share a common nomenclature (dB). This ambiguation between the two different descriptives leads to assumptions like you just made. One (dBv) describes a relationship of electronic voltage, the other (dB SPL) describes a quantity of a logarithmic measure of the effective sound pressure of a sound relative to a reference value. For sound in air, relative to 20 micropascals, the quietest sound a human can hear. (Another limit of human perception which measurement can surpass in scope). That knob does not relate to sound pressure levels. If the gain structure follows standards, a 3dB change in signal gain on a that preamp relates to about 6dB change is SPL. (However, the amount is dependent on many variables i.e., power, speaker efficiency, gain structure, etc.) So yes it makes sense you wanted to fall between the detents. Each click was well within the human perception limit.
The reason for measurement is to verify accuracy and quantify design criteria beyond that which our senses can determine. For instance, I can measure the THD of two different amplifiers, one tube based the other solid state. Obviously the Solid State would measure much lower THD. Same goes for IMD. But which one sounds better is a matter of the aesthetic and is not directly quantifiable. While the Solid State would be deemed more technically accurate, the higher THD in the tube amp sounds warmer. Why? Added harmonic content that is not in the recording, but instead is an artifact of distortion that happens to be rich in even harmonics. Harmonies in music are even harmonics and are naturally pleasing to the ear. But those harmonics produced by the tube amplifier are not on the recording. Therefore it can be said tube amplifiers, even ones close to being the theoretical perfect design, are less accurate.
After leaving the audiophile electronics game, I settled into making the recordings we all enjoy. I worked for a time on co-engineering Sheffield Labs recordings, working for Doug Sax. I was at the sessions and I know how those recordings sound. It is rare I hear those recordings sound correct on most hi-end systems. Funny thing is the more esoteric the system, the farther away is the reproduction from the sound of the recordings I know so well. I have the advantage of a true reference. I know the actual recordings, since I either worked on them or actually mixed them. I was the person responsible for deciding just how they were to sound. So my aesthetic is of course skewed towards a preference for accuracy, primarily because I have a legitimate reference. A starting point at the recording itself.
What constitutes a proper sound system is one that meets certain criteria for transparency. These are measurable and quantifiable parameters. Ideally, what comes from the source is reproduced with no artifacts from the system itself. A loudspeaker with a flat amplitude response, proper time alignment, and perfect phase coherency will be more accurate. An amplifier with the lowest practical distortion characteristics at the highest gain will be more accurate. A system with low noise and the highest possible dynamic range will be more accurate.
Now I mention this for two reasons. First, I have found myself in the dubious position of listening to a recording I sweated over for months. Fine tuning gobos and diffusers to capture a specific ambient field in the recording. Changing multitudes of microphones and microphone placements to get the right tone and placement in the image. Plus a multitude of other details. And the system I am listening to, some in the hundreds of thousand of dollar price range, are not even close to being able to resolve any of the details in the recording, or even maintaing tonality. And the proud owner turns to me and says, "So. What do you think?" Do I tell him? Most times I bite my tongue.
One circumstance like this was on a system featured in an article in a major audiophile magazine as one the best systems out there. All the big huge cables sitting on their respective telephone poll insulators, the machined aluminum chassis glistening in the special lighting set-up to show off the system. The reproduction of my recording was so poor I nearly pee'd myself. I'm thinking to myself, is this guys listening to the art, or the gear? Which leads to my second reason ...
Audio manufacturers and the people who worship their teachings will decsribe what they hear as "transparent" or "wholly accurate" or best still "musical". This last term really keys into the thinking, both to the purpose of profiteering companies or the justifications of gearheads. A piece of gear that "sounds musical" implies it is making music itself. A truley accurate piece of audio equipment shouldn't sound like anything. It should be transparent. So what we hear in this description are manufacturers cleverly disquising the less than accurate performance of their gear. The term being used by the audiophile desribes his desire to create a sound rather than to listen to the sound the artist created. The latter being a matter of hobbyist fun and aesthetic, which is fine. The former however is a simple deception for extreme profit which is unethical by nature. In other industries, it would be deemed criminal. Strong words, I admit. But honest ones. If it isn't we'd be paying $500 per gallon for gas. Come to think about it, that's way to low by comparision to audiophile margins. $5000? ... yeah that's about right.
My real peeve here is that claims are made that are outright lies. Problems that do not exist are fabricated, then products are designed and marketed at high prices to solve these non-existant issues. And what happens. People buy them and perceive some change. I know of at least three products that came on the market, as a joke by some of the manufacturers, just to see how far they could push the envelope. I was at the meeting for one of them. It is now an accepted thingee amongst audiophiles as a real essential tool, and it is a gag. A fabrication. What is known in the biz as a "guyver". Several other manufacturers no produce this thingee, some charging 1000 times for what was originally discussed as a wim around this table. I wish I could say, but it would violate my non-disclosure agreement I signed when I was hired. Most of you may have some of them. And many have perceived an "improvement". Proving the point that perception can be transient and open to suggestion. I assure you this thingee does absolutely nothing. And if I measure it, it would show nothing, regardless of the aural perception.
As audiophiles it is very easy for us to get caught up in hype, the gear and the next cool thingee. We sometimes forget about the music and art we are supposed to be listening to. The creative effort of the artists and engineers take a back seat to the sound of the system it's being played on.
OK ... I'm biased ... but honest. :-)
JRL
Edits: 11/03/12 11/03/12 11/03/12 11/03/12 11/03/12 11/03/12 11/03/12
"That knob does not relate to sound pressure levels. If the gain structure follows standards, a 3dB change in signal gain on a that preamp relates to about 6dB change is SPL."
A decibel is a ratio of power, not amplitude. Doubling the power adds 3 dB. Doubling the voltage quadruples the power and adds 6 dB.
Tony Lauck
"Diversity is the law of nature; no two entities in this universe are uniform." - P.R. Sarkar
Posted by jrlaudio (P) on November 3, 2012 at 06:57:05"A solid silver connector, or even solid nickel, is most likely better than a gold plated copper one for these reasons. All this comes from an engineers understanding of metalurgy and electro-chemistry,"
Later,
"Using a cable does not change its molecular structure, align molecules, or change in any physical way the wire or insulation.... It is much more easy for perception to be changed than the molecules of copper to be transformed by use"
Molecules of copper?
It's only easy if your deaf.
Edits: 11/07/12 11/07/12
you are overgeneralizing. In all my years of audio I can not recall any manufacturer claiming that the plating of a CONNECTOR contributed to the skin effect. All I read used gold primarily as an anticorrosive measure.
Still you claim that the plating has no audible effect . Have you actually tried this? I know you seem to distrust Cardas but the company offers ends available in a choice of silver gold or rhodium plate. Have you tried listening to identical cables made with the different ends? Or more cheaply, Mouser sells Deltron ends available in silver plated center pin or gold plated. While you claim no audible difference, I hear rather distinct differences, even though a file test reveals no significant differences in the base metal or the lower layers of plating.
Now you will claim that testing will reveal no difference. Could it be you need to test for something else? Theoretically, the only factors influencing cables are inductance, resistance, and capacitance. Yet we know that insulation dielectric has an effect or we would never bother with teflon, and not simply for the temperature resistance. What other parameters which exist could possibly have an effect?
In this, I am reminded of the head of the US Patent office , who in the late 1800's proclaimed that everything worth patenting had already been invented.
The most important factor you forget is the source material for music. Evaluating a sine wave is one thing; music is a another animal entirely. The interactions, overtones, all add a level of complexity no instrument I know of can measure.
Because recording quality can vary so much, what recordings do you use for evaluation? I have maintained for a long time now, that a truly neutral system will reveal the microphone set up of the session. That means one has to collect recordings with known recordings set ups ( they do exist, BTW: early Audio Quest recordings have photos of the recording s
set up, RCA early classical are well documented as are Decca, and Mercury). Using these recordings as a base, it is possible to obtain a relatively neutral set up.
That being said not all like to listen to these recordings. You could be a Linda Ronstadt buff as many of my acquaintances were in the 70's. You could set up your system to make her recordings sound fabulous, but not many others will sound the same. However, if you listen to her a lot, who's to say that it is wrong.
You look for accuracy, however your very own experience in making recordings seem to indicate otherwise. You openly admit your sense of aesthetics dominate the mike placement and acoustic control devices. Is that really accurate?
You say that Zobel networks eliminating RF effects are measurable and audible, yet earlier you state that RF frequencies are unimportant being that they lie beyond the range of human hearing. There is an inherent contradiction of your statements here.
And then I would raw your attention to the good old laws of thermodynamics. You know, the one that states energy can not be created or destroyed. What is wrong in transmuting that energy into a form more consonant to one's hearing? Since we can not eliminate it, why not change it to emphasize one's musical tastes?
obviously, YMMV
Stu
You wrote,"Audio manufacturers and the people who worship their teachings will decsribe what they hear as "transparent" or "wholly accurate" or best still "musical". This last term really keys into the thinking, both to the purpose of profiteering companies or the justifications of gearheads. A piece of gear that "sounds musical" implies it is making music itself. A truley accurate piece of audio equipment shouldn't sound like anything. It should be transparent. So what we hear in this description are manufacturers cleverly disquising the less than accurate performance of their gear. The term being used by the audiophile desribes his desire to create a sound rather than to listen to the sound the artist created. The latter being a matter of hobbyist fun and aesthetic, which is fine. The former however is a simple deception for extreme profit which is unethical by nature. In other industries, it would be deemed criminal. Strong words, I admit. But honest ones. If it isn't we'd be paying $500 per gallon for gas. Come to think about it, that's way to low by comparision to audiophile margins. $5000? ... yeah that's about right."
I couldn't help noticing you own a Koetsu Onyx cartridge - a cartridge noted for not only being extremely expensive on the overall scale of things but also for possessing a rather "romantic" sound, as it were. Kind of strange you would go off on such a long rant regarding high end prices and deception and ethics when you yourself bought one of the more famous examples of precisely what you are railing against.
Edits: 11/03/12
Ha ... true. It was a gift, from Oracle. From years back. I've upgraded it to a MkV from a MKIII.
I have yet to find a truely neutral cartridge, and doubt I will. But what I do like about the Koestsu is the tracking, and speed. And the imaging and phase coherancy is spot on. It is a bit warm having some dips in the upper midrange in its amplitude response. It's nowhere near what I'd like to have, but I havent found anything more neutral ... yet.
However, I noticed you didn't mention I use Bryston amps. Not expensive by audiophile standards, but absolutley transparent. What goes in is what comes out, just higher in level. Low THD, Low IMD, high damping factor, wide amplitude and frequency response, high current output down to DC, at almost any load. And a 20 year unconditional warrantee to back it up.
Nor did you mention I use a $1700 Apogee DAC. Unlike most of the audiophile DAC's it actually coverts to analog from whatever the source is. In other words (and I'm simplifying again) it coverts 24/192 directly to analog without any intermediary digital to digital down conversion. Most of the hi-end audio DAC's like the dCS take the 24/192, down-convert it to 16/44.1 then covert it to analog. Also all the clocks are 44.1 using multipliers to achieve higher clock rates. So you start with a clock at 44.1 with 10ppm accuracy, put it through multipliers 3 times to get 172 at an accuracy of 30ppm (maybe, the stability of the multipliers is not published). The Apogee internal clocks operate at all rates without multipliers and do so at a 1ppm accuracy. (Their external Master clock, called the "Big Ben", has an accuracy specified as "unmeasurable" since no test equipment exists yet that can measure to that degree, even at NIST.)
My Apogee cost about $1700 which is the retail price. Oh ... And it does A/D as well. And this is the cheap model. AND ... this is the converter used on about 95% of all the digital recordings made, and most of the digital mastering done. So I have zero jitter, because I use the same clock standard as was used to record the audio, master the audio, and make the CD, at whatever bit depth or sampling rate. And I can archive my LP's to digital using 24/192 because I have A/D.
But yeah ... I have an expensive romantic Koetsu.
JRL
"Most of the hi-end audio DAC's like the dCS take the 24/192, down-convert it to 16/44.1 then covert it to analog"
Huh? They may up convert the signal, e.g. 24/192 to 32/384 and then convert to analog. There are some DACs that down convert, but these are in no sense audiophile, e.g. DACs that use asynchronous resampling and convert 192 kHz to 110 kHz before converting to analog.
Tony Lauck
"Diversity is the law of nature; no two entities in this universe are uniform." - P.R. Sarkar
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