Any evidence wire is less than fully transparent at audio frequencies?

[esldude]

Does he have results showing that hitchhiking noise causing an actual change in the audio output - for example, by appearing directly on the audio output, or causing jitter of the DAC clock? It seems like a sensible addition to a DAC test suite - inject noise and jitter on the digital input to see how well the DAC rejects it.

 

Same question I have Don Hills. One which seems blindingly obvious to include. And one that seems curiously absent. I believe I recall Mr. Rankin saying he finds no measured difference in output, but insists it sounds different.

[esldude]

Does anybody have such evidence where the binary data is still "bit perfect"?

I understand that even Gordon Rankin hears differences, but has so far been unable to measure it at Audio Out.

This also applies to different Software players where the output remains "bit perfect"

Just because we have so far been unable to measure it at the audio output (?) doesn't mean that it doesn't exist.

 

Alex

 

Agreed it doesn't mean that it doesn't exist. But for the purposes of this thread it also doesn't mean they have evidence. Changing an upstream parameter, listening and judging it better while measuring no output change falls into the category of anecdote. If it is a real effect, it will be possible to determine it someway. Until then, they have anecdote, conjecture, not evidence. More investigation required if they wish to show it is an audible effect.

[mayhem13]

. In many cases the listeners are not familiar with the musical content, or the presentation of the equipment used.

 

So you're saying that one needs to be familiar with the content to discern a difference?....and in such cases where the differences are so minimal to be reduced to familiarity only......do you think there's value there? What becomes of the listener enjoying new or unfamiliar content on his own system? Is there a verification process for these instances?

 

While I appreciate your input on the validity of DBTs with a plausible reason for results unfavorable to audiophiles, even if plausible, the 'reason' isn't reasonable, but kinda silly.

 

As to presentation of the equipment, that's a pretty lame excuse and IMO insults the intelligence of your fellow forum members.

 

While the topic of unavailable evidence within the face or reason, I'm just not that interested in the area to consider its existence......not when the likelyhood of extraterrestrial intelligence is so much more interesting! I can't hear a difference no matter how hard I try, tweek or practice......but I'm pretty sure E.T. is out there.....somewhere.

[esldude]

Sorry, but your FACTS are NOT facts, they are only YOUR belief.

It says more about the unsuitability of DBT testing in unfamiliar listening surroundings and conditions, than anything else. In many cases the listeners are not familiar with the musical content, or the presentation of the equipment used.

 

 

Come on Alex those are facts. There is a theory about how signals propagate on wire at audio frequencies. Predictions it makes on how that works are based upon well supported physical properties and corroborated by measurement. Those are facts. Those reliably predicted results indicate at audio frequencies nothing is going on that would sound different. Blind testing indicates the same. You may choose not to believe those facts, but you lack the evidence I am asking for in this thread. You may be right, but so far the facts available say otherwise. If someone can garner the evidence, and show how this occurs then that is one thing. Thus far there seems a lack of evidence beyond the anecdotal.

[sandyk]

Agreed it doesn't mean that it doesn't exist. But for the purposes of this thread it also doesn't mean they have evidence.

 

Dennis

We both know, as many other members do too, that irrefutable evidence is presently unavailable. So given that, what is the rationale behind starting a divisive thread like this ? Are you hoping that somebody will post the leaked results of research in this area?

If there are such results available, they are most likely being withheld for purely commercial reasons.

You may as well ask "how long is a piece of string." (grin)

 

Come on Alex those are facts.

 

 

That reminds me again of the story of a little boy standing on a street corner , with a sign saying "FACTS , only 5c each."

A stranger took pity on the little boy and bought one. He opened the package and said to the little boy "This is only a turd wrapped in paper"

To which the little boy replied "That's a FACT "

 

Regards

Alex

[GregWormald]

If all you want to use to determine "audibility" is LCR then the evidence for cable difference (probably) doesn't exist.

 

Please remember that **our** audio system--ears, brain, rest of the nervous system--has developed some amazing capabilities that have kept the human race alive and functioning for tens of thousands of years and (probably) isn't limited to LCR effects.

 

In the end, if it pleases you, use it.

 

Greg

[esldude]

Dennis

We both know, as many other members do too, that irrefutable evidence is presently unavailable. So given that, what is the rationale behind starting a divisive thread like this ? Are you hoping that somebody will post the leaked results of research in this area?

If there are such results available, they are most likely being withheld for purely commercial reasons.

You may as well ask "how long is a piece of string." (grin)

 

 

 

 

That reminds me again of the story of a little boy standing on a street corner , with a sign saying "FACTS , only 5c each."

A stranger took pity on the little boy and bought one. He opened the package and said to the little boy "This is only a turd wrapped in paper"

To which the little boy replied "That's a FACT "

 

Regards

Alex

 

Alex, glad to hear you say it.

"irrefutable evidence is presently unavailable."

 

The rationale behind this thread is transparent. I don't know of any good evidence, and wondered if there was any. So far not. I was hoping for some if it is out there. Privately held for commercial reasons or otherwise. Of course I am leaning toward 'lack of evidence' being withheld for commercial reasons.

[esldude]

If all you want to use to determine "audibility" is LCR then the evidence for cable difference (probably) doesn't exist.

 

Please remember that **our** audio system--ears, brain, rest of the nervous system--has developed some amazing capabilities that have kept the human race alive and functioning for tens of thousands of years and (probably) isn't limited to LCR effects.

 

In the end, if it pleases you, use it.

 

Greg

 

No you have it backwards. I have made no pre-ordained idea that LCR is all I want to use. Physics of electrical signals on wire have shown LCR is all one needs to use. If the typical wire use for audio doesn't curtail anything close to audio frequencies, doesn't add any distortion at any level that matters, doesn't seem to alter the signal, then our evolved hearing will hear no effects of the wire as there aren't really any to hear.

[Jesus Montana]

I work in consumer research. Anytime you are testing groups of people at the same time in the same room you can chuck the results. Any testing with a human element is flawed, you are just trying to minimize flaws as much as possible. I can't even imagine the expense of trying to get accurate results testing audio equipment.

 

Who would pay for this?

 

The BBC bank-rolled testing 40-50 years ago which was so long ago that improved methodology has most likely eclipsed any result, unless they got very lucky.

[sandyk]

If the typical wire use for audio doesn't curtail anything close to audio frequencies, doesn't add any distortion at any level that matters, doesn't seem to alter the signal, then our evolved hearing will hear no effects of the wire as there aren't really any to hear.

 

Don't forget that to use a "wire" you also need to use a plug at each end. In the case of digital audio, the plug should also be 75 ohms impedance. Then there is the type of solder used to terminate the wire to the plug, (smirk) or perhaps it is a compression type plug, which in my experience can go high resistance. A wire does not a cable make, all by itself. There are many reasons including L,C and R why cables of the same length can sound a little different. Of course, if you believe that "Oxygen Free Copper" is only used so that manufacturers can charge a higher price for their cables ......

[sandyk]

So you're saying that one needs to be familiar with the content to discern a difference?....and in such cases where the differences are so minimal to be reduced to familiarity only......do you think there's value there? What becomes of the listener enjoying new or unfamiliar content on his own system? Is there a verification process for these instances?

 

Mayhem13

I believe that David (Audiophile Neuroscience) has covered this area far more eloquently and thoughtfully than I ever could, in his very popular thread. Many members will tell you that one needs to be familiar with the content to discern a difference

under stressful DBT conditions ,as distinct from normal relaxed listening. Familiarity with one's own equipment in familiar surroundings is a great advantage too.

 

As to presentation of the equipment, that's a pretty lame excuse and IMO insults the intelligence of your fellow forum members.

 

That's utter garbage , unless you believe all amplification meeting certain minimum standards sounds the same, and that includes both digital and analogue amplifiers. If you want to believe that a typical Class D amplifier with around .01% distortion sounds the same as a good analogue amplifier with around .0005% distortion, then it is pointless further discussing this with you. Then there is the question of the loudspeakers, where there can be vast differences in how they sound, especially to those listening off axis.

Neither have we even touched on the quality of the source material, and the device used for playback.

It wasn't so long back that Archimago (IIRC) presented a couple of digital musical tracks for comparison, where they weren't even pure digital, as you could clearly see the noise floor and bias waveform of the recording deck at around -70dB in a sound editing program.

 

Alex

[gmgraves]

Yes, I have noticed.

 

Several times been tempted to start a thread discussing cable company white papers. But as several advertise here I demurred.

 

I think you're probably OK if you don't mention the companies involved by name. You are right about one thing. We don't want to get Chris in dutch with his advertisers. Not good!

[gmgraves]

Sorry, but your FACTS are NOT facts, they are only YOUR belief.

It says more about the unsuitability of DBT testing in unfamiliar listening surroundings and conditions, than anything else. In many cases the listeners are not familiar with the musical content, or the presentation of the equipment used.

 

Sorry to disappoint you, but the facts are facts. The fact that you choose to ignore them is your belief, not mine. And while the idea that DBTs are unsuitable for testing this stuff is certainly a possibility, there is no scientific reason to suppose that a methodology that has proved valid for all other scientific inquiries is invalid for audio. In fact, the evidence supports just the opposite point of view.

 

One thing that I will say in support of the possibility of your assertion is the equally valid fact that it is extraordinarily difficult to set-up a proper DBT which will return anything but a null result - even on things over which there should be no controversy like amplifier sound or DAC sound. It is possible, you understand, but most individuals don't have the discipline, the equipment, or the methodology to do it well enough.

 

However, in the case of cable sound, the physics, the mathematics, and the DBT results all agree to such an extent that it is highly unlikely that they could be wrong. Cable is a simple conductor. It is either fully transparent or it isn't (and therefore not a conductor). If cables are fully transparent, then a correctly executed DBT will return a null or "no difference" result. If one or more is not transparent, then there will be a difference, where the non-transparent cables will sound worse, by some degree than the fully transparent full conductor cables. But I don't imagine that many manufacturers would stay in business long by selling cables that purposely less than full conductors. Nobody wants to make a product that is worse than a $2.00 throwaway interconnect.

[sandyk]

George

Seeing you believe that YOUR facts are FACTS . Would you also state that it is a FACT that 2 .wav files with identical check sums can't sound different ?

Alex

[Jud]

Same question I have Don Hills. One which seems blindingly obvious to include. And one that seems curiously absent. I believe I recall Mr. Rankin saying he finds no measured difference in output, but insists it sounds different.

 

I don't know if Gordon Rankin even mentioned any differences in input measurements. My general recollection is that he said pretty much that he heard differences he couldn't account for with the measurements he'd done (whatever those were).

 

I hope my rather non-specific memories aren't unintentionally misrepresenting what he said.

[Jud]

Yeah, I was thinking in audio that at least conceptually there might be a lower level effect on much shorter time scales, but still enough to affect timing of analog and digital signals. But I haven't read enough to know whether this may apply to modern day audio cables.

 

Ran across something more recent that might be describing the same effect with specific reference to audio - Walt Jung and Richard Marsh (then of Lawrence Livermore National Laboratory, since then an audio designer for companies like MIT, and eventually his own company) talking about "dielectric absorption" in capacitors:

 

Dielectric absorption becomes a critical factor in circuits which are highly dependent upon speed of response. As the a.c. signal goes to zero (as in a short circuit) the trapped or bound electrons within the dielectric do not follow as fast. These electrons take a finite time to move from the dielectric to the electrode. As capacitors are typically used in audio circuitry, we could translate these defects into loss of accuracy in reproducing the fine inner detail of music, as well as the music's dynamic structure.

 

It is quite illuminating to consider what effect a phenomenon such as DA will have on an a.c. signal consisting largely of transients (such as audio) might have. For example, when an a.c. voltage is applied, there is a tendency for the dielectric absorption phenomenon to oppose this change in polarity.

 

When music is the a.c. signal, the sonic degradation is one of compression or a restriction of the dynamic range. Also, a loss of detail results, and the sharpness is noticeably dulled. With dielectric types which have high DA, there is a definite "grundge" or hashy distortion added to the signal.

 

It is quite important to describe the sonic thumbprint that DA contributes to subjective audio. The effects of DF and DA can be perceived differently. DF is primarily a contributor to phase and amplitude modulation DA reduces or compresses dynamic range. This it does by not returning the energy applied all at once. With signal applied to a capacitor with DA present, the amplitude is reduced by the percent DA. When this energy does get returned (later), it is unrelated to the music and sounds like noise or "garbage" being added; the noise floor is also raised. High-frequency and/or transient signals are audibly compressed the most. Signals that look like tail pulses (a lot of transient music information is of this nature) are blunted or blurred in their sound. "Dulling," "loss of dynamics," "added garbage or hash," and "an inability to hear further into the music" have been subjective terms used to describe the DA effect in capacitors.

[Jud]

Same question I have Don Hills. One which seems blindingly obvious to include. And one that seems curiously absent. I believe I recall Mr. Rankin saying he finds no measured difference in output, but insists it sounds different.

 

I do have a proggy that adds simulated jitter which, along with your file, Dennis [embarrassed shrug] I have not gotten around to testing yet.

[Jud]

"Thinking here of USB cables and how many/most such cables are manufactured with power and signal leads in very close proximity over the length of the cable."

 

Yes, true, but the digital lines in USB are differential and will be somewhat resistant to that noise. And while such noise can ride over USB, part of the beauty of digital is to not be bothered by noise below a certain level. Certainly the bit transmission is unaltered as the bits make it across in even the cheapest conforming USB cables. So any effects are secondary or tertiary effects which seem to be pretty far down in level to make an audible difference. The raw timing doesn't even need to be especially good over USB implementations where the data will be clocked out anew by a local clock. You are down to saying enough noise rides across to effect that local clocking out of the data to have audible effects. Which is what a few designers say. I haven't seen good data as to what level those effects are occurring.

 

Just conceptually, I could also see noise affecting amplitude of the "bits" short of causing dropouts sufficiently to alter the timing of transitions across the zero crossing point. I don't know whether this would be remedied by the DAC's buffer and clock.

 

The other possibility would be noise getting into the ground plane and from there into the analog side of the system. I imagine galvanic isolation should minimize such problems, but as always it depends on the quality of both design and implementation.

[rennq]

You start a thread with a question you claim (incessantly) you already "know" the answer to, and also claim you're not trolling. If you already "know" the answer, but post a controversial question anyway, then you are trolling.

[Daudio]

I understand that even Gordon Rankin hears differences, but has so far been unable to measure it at Audio Out.

 

Alex,

 

This is an objectivist thread, and Dennis set the rules at the outset, so please let them have their fun without distraction.

 

Then, maybe, they will have the respect to leave subjective threads alone and not continually rain on those parades !

 

Set a good example, have some respect, and some hope

[gmgraves]

George

Seeing you believe that YOUR facts are FACTS . Would you also state that it is a FACT that 2 .wav files with identical check sums can't sound different ?

Alex

 

Let me answer that by asking you a question. If you had two copies of MS Word, and both had identical checksums, would you state that those two copies of the application won't have different feature sets, or that one will open and the other won't? Because I'll guarantee you that the MS Word Application is FAR more complicated, digitally, than any WAV file.

 

If your two WAV files are played through the SAME hardware chain, they HAVE to sound the same because they are the same. Just like any other digital file.

 

And my facts are facts. That you might not buy them is another subject altogether and speaks to the realm personal belief. It has nothing whatsoever to do with facts or reality or even logic - like most religious delusions.

[gmgraves]

Alex,

 

This is an objectivist thread, and Dennis set the rules at the outset, so please let them have their fun without distraction.

 

Then, maybe, they will have the respect to leave subjective threads alone and not continually rain on those parades !

 

Set a good example, have some respect, and some hope

 

Actually, I'm only partly an objectivist. IOW, when the evidence against the subjectivist religious belief that cables have a sound, and that expensive ones sound "better" than cheap ones and the physics and maths say that it's not possible, and even DBTs back up the scientific prediction that they can't sound different, then I have to acquiesce to reality. On the other hand, there is no scientific reason why amplifiers, CD players and DACs should all sound the same as they are complex bits of kit designed from different viewpoints using different components and in spite of what many objectivists contend, all of these components' anomalies are NOT below the threshold of audibility even thought many are and many more are damned close. Until all anomalies and distortions are below the threshold of audibility, there is simply no way that anyone can make a air-tight case for all of these active components to sound alike.

[The Computer Audiophile]

Well, here is a general discussion that quotes a lot of sources and tests:

 

Cables, Interconnects and Other Stuff - The Truth

 

And here are the results of some ABX tests of speaker wire and interconnects that show that there is no statistical difference between cheap interconnects and expensive ones and zip cable and expensive speaker wires.

 

ABX Double Blind Tests: Interconnects and Wires

 

I am quite surprised by the fact that there isn't more info of tests like this available on the web. I know that these types of DBTs have been done often, all over the world by organizations like the Boston Audio Society, The Bay Area Audio Society, but they don't maintain extensive archives on line.

 

These above results certainly tally with DBT cable tests that I have been involved in. The first cable DBT that I was involved with was when I was writing for Stereophile. At the Long Beach Stereophile show one year, a number of the contributing editors (of which I was one) were involved in an ABX test of interconnects. The results were null, I.E. they were the same as blind chance, flipping a coin, etc. Since then I have both help set-up and also participated in a number of interconnect DBTs all with the same result. The most recent was about six months ago. One of our group of audio nuts had just bought a set of 1 meter Nordost Valhalla interconnects. Convinced that these $4000 wires would beat all comers, he suggested a DBT against a number of different cables, and everybody brought their best. Also included was a $5 pair of RG59 interconnects purchased from MyCableMart.com. Cable after cable was substituted in position "A" while the Nordosts remained in position "B". No one could hear any discernible difference between any of them - just as I suspected and expected.

 

While none of this absolute proof of anything, the sum total of people's experiences coupled with the physics and the maths, certainly points to a basic truth here, and that is that correctly made cables have no sound. And incorrectly made cables can only sound worse.

 

I'm not trying to shake anybody's audio belief system with this info, but I do think that people should be armed with some facts before venturing forward with their cable evangelism.

Hi George - Thanks for the links. Armed with this information I am puzzled why your are 100% certain no differences in "correctly" made cables can exist. The tests in the links are nothing on which I would base an absolute opinion.

 

For the sake of discussion, if you were listening for evidence of the smallest audible changes possible would you listen on a system and in a room with which you weren't intimately familiar? Listening at a Stereophile show for sonic differences in cable can be a major disservice to the listener and anyone reading the "results".

 

I'm not arguing about cables, rather the fact that your 100% absolute opinion is based on, what I consider, less than desirable evidence.

[gmgraves]

You start a thread with a question you claim (incessantly) you already "know" the answer to, and also claim you're not trolling. If you already "know" the answer, but post a controversial question anyway, then you are trolling.

 

Actually, I don't see that anyone has started this thread by claiming that they already know the answer. What I see is someone who asked the following question (I'm paraphrasing for clarity, here): Physics and mathematics say that properly designed cables cannot, by definition, have a sound. Yet many of you claim that in spite of that evidence, cables do have a sound - and you discount the role of expectational or sighted bias in providing those "differences." Does anyone have any theoretical or practical evidence (the results of real research - not anecdotes) to back-up this assertion?

 

It seems to be a reasonable question to me and not at all a troll. After all, extraordinary claims require extraordinary proof. Or would you rather not know myth from reality? If that is true, then how does the belief in cable sound differ from religious belief? Both require that adherents believe in something that not only cannot be proved, but which actually flies in the face of what we know to be true. Both beliefs rely on the maxim that one cannot prove a negative (for instance, I cannot prove that cables have no sound, I can only point out the physics and mathematics and test results that tell us that the proposition is highly unlikely. If you still insist that you hear a real difference, then who am I to tell you that you don't) and both rely strongly on faith in something.

 

If this question is ever going to be settled, then some real research on the side of the true believers must be done. Since no one can prove a negative, then the onus is on the subjectivist side to show that differences do exist by actually proving it and it seems to me that's what the O.P. was asking for.

[The Computer Audiophile]

After all, extraordinary claims require extraordinary proof.

I used to buy into that statement. Recently I've changed my mind.

 

Why wouldn't all claims, ordinary or extraordinary, simply require proof?