Yes, it is true, I can't hear much with certain ABX boxes in my system, especially blind. I guess I should give up and do something else for a living. Tom Holman and Dave Spiegel made that decision, 30 years ago. I wonder if the Grateful Dead will take me back? ;-)
Thanks SY and John, my brain is truly squirming now....
So, since LCR is the meat of the issue and I am pretty sure that C is the real culprit and that within C the dielectric constant is the evil tool and within dielectric constant, the charge acceptance threshold, release threshold and the quantity of electrons per square cm are the mechanism for any sort of change in the sonic character of an AC signal, in a constructed cable with ample dielectric material, my assumption is that one constructed with known and very small amounts of C might actually be a positive control.
Not at all sure how we could have any sort of positive control from just listening, just because all of that information can only come from listening, which is the real item under test here. I will PM Tom and see if he is at all interested. Again, thanks for the brain squirm.
Bud
So, since LCR is the meat of the issue and I am pretty sure that C is the real culprit and that within C the dielectric constant is the evil tool and within dielectric constant, the charge acceptance threshold, release threshold and the quantity of electrons per square cm are the mechanism for any sort of change in the sonic character of an AC signal, in a constructed cable with ample dielectric material, my assumption is that one constructed with known and very small amounts of C might actually be a positive control.
Not at all sure how we could have any sort of positive control from just listening, just because all of that information can only come from listening, which is the real item under test here. I will PM Tom and see if he is at all interested. Again, thanks for the brain squirm.
Bud
SY, have any idea of the specs yet?
Andre, I will have to replace the RCA end pieces on a pair of cables and then I can send them to you for evaluation. I normally use the cheapest Radio Shack plug ends because they have the least amount of metal and the least pathological moldable plastic, as there handle and shroud
(polypropylene). They really are junk though. You might PM me with an address.
Bud
Andre, I will have to replace the RCA end pieces on a pair of cables and then I can send them to you for evaluation. I normally use the cheapest Radio Shack plug ends because they have the least amount of metal and the least pathological moldable plastic, as there handle and shroud
(polypropylene). They really are junk though. You might PM me with an address.
Bud
It could be serve as a positive control, but first only after it was shown that it has an audible effect and second that the audible effect wasn´t dramatic. 🙂
As you want a test with high sensitivity you want to use positive controls that need high sensitivity to produce a positive result. 🙂
But otherwise i´m glad that you noted the very interesting switch in the discussion during the last couple of days. 🙂
Wishes
"Science and Subjectivism in Audio."
Douglas Self Site
article that appeared in the UK journal Wireless World for July 1988 ,about the so called audio "voodoo" path the hi-fi world as taken as of late.
thats before 20 years ,Now it is far ... FAR worse.
About cables :
"Passing an audio signal through cables, PCB tracks or switch contacts causes a cumulative deterioration. Precious metal contact surfaces reduce but do not eliminate the problem. This too is undetectable by tests for non-linearity." - This is the belief.
Answer :
Concern over cables is widespread, but it can be said with confidence that there is as yet not a shred of evidence to support it. Any piece of wire passes a sinewave with unmeasurable distortion, and so simple notions of inter-crystal rectification or "micro-diodes" can be discounted, quite apart from the fact that such behaviour is absolutely ruled out by established materials science. No plausible means of detecting, let alone measuring, cable degradation has ever been proposed.
The most significant parameter of a loudspeaker cable is probably its lumped inductance. This can cause minor variations in frequency response at the very top of the audio band, given a demanding load impedance. These deviations are unlikely to exceed 0.1 dB for reasonable cable constructions. (eg inductance less than 4 uH) The resistance of a typical cable (perhaps 0.1 Ohm) causes response variations across the band, following the speaker impedance curve, but these are usually even smaller at around 0.05 dB. This is not audible.
Corrosion is often blamed for subtle signal degradation at switch and connector contacts. By far the most common form of contact degradation is the formation of an insulating sulphide layer on silver contacts, derived from hydrogen sulphide air pollution; the problem seems to have become worse in recent years. This typically cuts the signal altogether, except when signal peaks temporarily punch through the sulphide layer. The effect is gross and completely inapplicable to theories of subtle degradation. Gold-plating is the only certain cure. It costs money. A switch with gold-flashed contacts can cost five times as much as the silver version.
Douglas Self Site
article that appeared in the UK journal Wireless World for July 1988 ,about the so called audio "voodoo" path the hi-fi world as taken as of late.
thats before 20 years ,Now it is far ... FAR worse.
About cables :
"Passing an audio signal through cables, PCB tracks or switch contacts causes a cumulative deterioration. Precious metal contact surfaces reduce but do not eliminate the problem. This too is undetectable by tests for non-linearity." - This is the belief.
Answer :
Concern over cables is widespread, but it can be said with confidence that there is as yet not a shred of evidence to support it. Any piece of wire passes a sinewave with unmeasurable distortion, and so simple notions of inter-crystal rectification or "micro-diodes" can be discounted, quite apart from the fact that such behaviour is absolutely ruled out by established materials science. No plausible means of detecting, let alone measuring, cable degradation has ever been proposed.
The most significant parameter of a loudspeaker cable is probably its lumped inductance. This can cause minor variations in frequency response at the very top of the audio band, given a demanding load impedance. These deviations are unlikely to exceed 0.1 dB for reasonable cable constructions. (eg inductance less than 4 uH) The resistance of a typical cable (perhaps 0.1 Ohm) causes response variations across the band, following the speaker impedance curve, but these are usually even smaller at around 0.05 dB. This is not audible.
Corrosion is often blamed for subtle signal degradation at switch and connector contacts. By far the most common form of contact degradation is the formation of an insulating sulphide layer on silver contacts, derived from hydrogen sulphide air pollution; the problem seems to have become worse in recent years. This typically cuts the signal altogether, except when signal peaks temporarily punch through the sulphide layer. The effect is gross and completely inapplicable to theories of subtle degradation. Gold-plating is the only certain cure. It costs money. A switch with gold-flashed contacts can cost five times as much as the silver version.
The claimant normally just claim to hear a difference, but does not exclude any possible reason (despite maybe the obvious, that the electronic device does not sound like a police wistle suddenly due to an instability issue).
In fact i wasn´t vague about the positive controls, in reality i gave even explicite examples what to use as such.
I surely didn´t remember every text written anywhere on this topic, but this one i do remember because it is such an unitentionally interesting example.
First, one might suspect that it isn´t a sufficient test run, if you ask a participant whose detection ability was not proved (lack of positive control), or as seen later, has shown to miss the positive control.
At the end of that article Lipshitz talked about a switching noise from the ABX box, that was present and could led to positive identification, but that nobody else noticed before.
(I´ve cited that already maybe a couple of hundred pages before 🙂 )
I´d draw the conclusion from this fact that the sensitivity level of the participants wasn´t high enough.
Of course one could argue, that the listeners were concentrated on something coming from the speakers not from the switching box, but i don´t buy that. It just illustrates the fact, that the listeners (not trained for listening under the specific blind test conditions) were not in a sufficient state of awareness that is needed to detect any audible difference.
Second, i choose for example the Meyer/Moran test, published in the JAES; the journal article did not mention any test of the devices used (and btw provided quite surprising no measurement of any device nor from the music samples used), but there exists an addendum at the boston audio society website:
BAS Experiment Explanation page - Oct 2007
A quote from that:
"When the subject was listening to the high-bit audio alone, whether sighted (with the display showing A) or blind (with the display showing X), our test system added the following components in series with the high-bit player’s output: (1) an ordinary RCA connecting cable 18 inches long, and (2) a switchbox comprising two RCA connectors, a total of 4 inches of hookup wire, and a reed relay with 0.2-ohm dc resistance.
None of the subjects, including the owner of the audiophile-grade System 4 described below, felt that the addition of these components changed the sound of the high-bit audio in any way."
(bold feature added by me)
There might be exceptions, but i´m not aware of a test using a sufficient positive control in which a switch box has been tested.
Wishes
In fact, a positive control can be used in the way you´ve described above, but of course is not restricted to that. Auplater later quoted the whole paragraph, but now an excerpt of the wikipedia entry on experimental design will do:
The effect we are looking for is an audible difference that occurs after the change of cables.
As in an double blind listening test the listener (who is an integral part of our experiment) is as much under test as the EUT, we have to ensure that the listener has the highest possible sensitivity for audible differences under blind test conditions.
Therefore my proposal to use positive controls for example from Paul Frindle´s list (who claimed to have confirmed quite small differences to be audible in ABX tests) or small amplitude response variation around 0.1dB (you earlier did point to the fact that level differences that small normally would be percepted as _sound_ difference not as level differences 🙂 ), or use the difference between two cd-players that have been confirmed to be audible.
Wishes
P.S. As i renewed my suggestions already a lot of times, can i suppose that any further comment from you that my proposals were vague, would qualify for _dishonest_ discussion habits?! 🙂
... but your memory played tricks on you: it wasn't switch noise from the ABX. It was noise from the Sony PCM-1 that was switched in and out of the circuit. In circuit he heard the PCM noise that was absent out of circuit. That helped him identify when the PCM was in-circuit. Others, that missed the noise, couldn't hear any difference with a an AD/DA box in the system or not.
jd
Positive nothing
In my opinion, these would not qualify as "positive controls"; more like another treatment combination to ascertain the effects of changing the SOURCE information and determining whether or not such SOURCE modifications may confound the outcome. Different experiment altogether.
To me, the positive control needs to be a cable/device that exhibits the kind of response proponents of cable sound promote (minute changes in timbre, difference in imaging, improvements in micro-details, that sort of thing) in a measurable and controlled manner that can be quantified.
Your proposed "positive control" does not address any of these at all
John L.
In my opinion, these would not qualify as "positive controls"; more like another treatment combination to ascertain the effects of changing the SOURCE information and determining whether or not such SOURCE modifications may confound the outcome. Different experiment altogether.
To me, the positive control needs to be a cable/device that exhibits the kind of response proponents of cable sound promote (minute changes in timbre, difference in imaging, improvements in micro-details, that sort of thing) in a measurable and controlled manner that can be quantified.
Your proposed "positive control" does not address any of these at all
John L.
While i would think, that regarding to the sensitivity of the listeners it did not make a difference if they failed to detect the hiss or the switching noise, you are right, Lipshitz wrote about the higher noise from the pcm. 🙂
But, he also wrote about the relay ´click sound´, but that was detected by Vanderkoy:
"I expressed my desire to try the test, and Remington went to cue up the record again, but I requested to be allowed to undertake the test with no signal passing though the system. Before realizing the import of what he was saying, Vanderkooy interjected: "Ah! You're going to listen to the sound of the relays." Yes, there is indeed a slight audible difference between the acoustic "click" made when the "A" and "B" relays pull in. This is due to the unavoidable differences in the mounting positions of the relay on the A/B/X box chassis and, although slight, it can be heard if one listens for it. I replied that I was going to listen to the difference in background hiss, and the subsequent series of blind trials showed conclusively that the two signal paths could be reliably distinguished on this basis alone."
quoted from:
Boston Audio Society - ABX Testing article
Wishes
But again, you evaded the issue of an appropriate positive control. The claim, for the 10,000,000th time is, "I can hear a difference between wires/cables/interconnects/whatever that is NOT due to mundane factors." Now, what is an appropriate positive control for a wire test, something in wires unrelated to the mundane variables, that has an established threshold?
Why do you think so?
What you quoted above as response proponents can be subsumed as sound differences and of course reported are a full bag of other possible differences (like faster, clearer, more dull, exaggerated bass and so on), and that is exactly what the positive controls proposed will deliver.
Please remember that level differences that small will be percepted as sound differences; on the mentioned list from Paul Frindle´s paper you will find audible distorstion as low as -80dB, level differences as small as 0.05dB.
Or take for example the difference between an old philips cd player and third generation sony cd-player mentioned on the abx web site.
Normally a difference between two different devices will be described with respect to differences in the "sonic signature" of each device.
But of course other controls are thinkable, but there some requirements that must be fullfilled.
Wishes
Your question is extremely easy to answer! Although subjectivists don't outright dismiss science, measurements or specs, they don't primarily embrace them. Subjectivists do not claim their method is scientifically oriented. A subjectivist allows their ears to be the final judge.
While an objectivist primarily embraces science, measurements or specs. Objectivists claim their methods are scientifically oriented. A objectivist allows a DBT to be the final judge. Thus it's the very science and objectivity they embrace that demands the DBTs be criticized if not done properly!
Thetubeguy1954
~Rational Subjectivism. It's An Acquired Taste!~
Hello auplater!
Why the insistance of having unknown variable added i.e., an ABX box? This ABX box is never part of anyone's home audio system! The wires ---{which are the device actually being tested}--- can easily be manuelly switched without providing any Clever Hans clues provided proper protocols are followed!
I know, I know, not adding an unknown variable and only testing the wires... it's just not fair, right??
Thetubeguy1954
~Rational Subjectivism. It's An Acquired Taste!~
The ear as the final judge is fine as long as you realize and accept the unreliability of such a bassis of belief. To believe ears are infalible is simple too nieve to even be discussed.
No test done improperly is worth reviewing whether done by a subjectivist or and objectivist. The objectivist must hold himself to the same standards that he requires of others. It's the subjectivist that does not seem to have that requirement.
Hello Janneman, Why? The answer is quite simple. Because the DBT doesn't require an unknown variable such as an ABX and extra wires added to the test and the system! The DBT can easily be done without one. Then I listen to see if I hear a difference just between one wire and another. Isn't that straightforward?
Personally I'm beginning to think now that someone has stepped up and accepted the challange to prove they can hear a difference in wires, you "supposedly" objective, scientifically oriented, measurements & specs guys are getting nervous.
You all know from the very beginning one of my stipulations was the wires be manuely switched sans an ABX box. This new almost insistance about the ABX box being added is a good way of trying to sabotage the the coming DBT and prevent the "truth" (whatever that may be) from coming out!
Thetubeguy1954
~Rational Subjectivism. It's An Acquired Taste!~
While there is normally no way to avoid scientific standards, which must be used to test hypothesis, it unfortunately is true that at least in the field of audio test methodology quite often is not on par with these standards.
Furthermore it seems to exist a general unwillingness to replicate tests done by others to see if the results were reliable. Therefore quite often newer test results were in contradiction to older studies but no one ever tries to find explanation for that.
Otoh every designer has his own working hypothesis and wouldn´t be able to work if he could only evolve his product by using double blind tests.
And if double blind test will not help to raise the sales figures of any product, than it is questionable if someone will pay for extensive tests.
Wishes
@ thetubeguy1954,
that is simply a misunderstanding; our ongoing discussion about ABX switch boxes and their possible influence is in no way related to your test with SY. 🙂
In this thread we are dealing with a whole bunch of topics in different states of discussion.
Wishes
that is simply a misunderstanding; our ongoing discussion about ABX switch boxes and their possible influence is in no way related to your test with SY. 🙂
In this thread we are dealing with a whole bunch of topics in different states of discussion.
Wishes
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