[kwkarth]

Am I to assume that Elliot Sound Products are the be all / end all authority on all things audio? I'm certainly not saying that everything they say is incorrect, but...

There seems to be a lot more wiggle room in their verbiage, in places, than there is in yours, such as phrases they are fond of using, eg. "There are differences between capacitors, but they are not (generally) audible - despite the claims." and frankly there are a myriad of questions that much of their prose generates. They, like many, make blanket pronouncements well beyond the scope of their apparent experience.

They're certainly not alone, as we well know.

Maybe I'm just stupid, but the more years I live, the more I see the scope of human knowledge being expanded among those who have not yet closed their minds. I can claim from experience that the more I learn, the more I know that I don't know.

 

[kwkarth]

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Originally Posted by Koyaan I. Sqatsi /img/forum/go_quote.gif Rod ate my dingo! se

Bummer mate!

 

[kwkarth]

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Originally Posted by Koyaan I. Sqatsi /img/forum/go_quote.gif A TDR? se

yupper, we used to make 'em @ Tek.

 

[Steve Eddy]

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Originally Posted by kwkarth /img/forum/go_quote.gif yupper, we used to make 'em @ Tek.

Yeah, I know.

But...

A TDR?

I'm just wondering what you think one might reveal that would be relevant to the audio band.

se

 

[kwkarth]

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Originally Posted by Koyaan I. Sqatsi /img/forum/go_quote.gif Yeah, I know. But... A TDR? I'm just wondering what you think one might reveal that would be relevant to the audio band. se

Impedance bumps in an improperly terminated cable for instance. Connectors and termination make a difference.

 

[Steve Eddy]

Quote:

Originally Posted by kwkarth /img/forum/go_quote.gif Impedance bumps in an improperly terminated cable for instance. Connectors and termination make a difference.

In the audio band?

Or are you talking about USB cables or something?

se

 

[kwkarth]

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Originally Posted by Koyaan I. Sqatsi /img/forum/go_quote.gif In the audio band? Or are you talking about USB cables or something? se

Audio cables. There was a great article in one of the audio rags a few years ago about the issue of treating (or not) audio interconnects as transmission lines. They showed how reflections that occurred because of impedance mismatch (which has to happen with todays standards) alteration of audio passband was created. This in their reasoning, was why some interconnects happenstantially sounded better or at least different from others. Anyway, that was my thought on the matter of TDR for audio cables, btw, you can identify cold solder joints easily this way.

Cheers!

 

[Steve Eddy]

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Originally Posted by kwkarth /img/forum/go_quote.gif Audio cables. There was a great article in one of the audio rags a few years ago about the issue of treating (or not) audio interconnects as transmission lines.

If you're talking about the one in Stereophile by I believe it was Herve Deletraz, it was a misguided and misleading article.

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They showed how reflections that occurred because of impedance mismatch (which has to happen with todays standards) alteration of audio passband was created.

It didn't show that.

The line was pinged with a very fast risetime pulse, just as is the case with a TDR. It wasn't pinged with any audio bandwidth signal.

You wouldn't be able to get any appreciable reflections or impedance mismatches in the audio band. Not unless your cable was tens of miles long.

Hell, cables don't even have a characteristic impedance at audio frequencies. That's why they're evaluated using lumped, rather than distributed parameters.

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This in their reasoning, was why some interconnects happenstantially sounded better or at least different from others.

But the reasoning was misguided. I even wrote JA at the time telling him I was surprised that Stereophile would even print such an article.

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Anyway, that was my thought on the matter of TDR for audio cables, btw, you can identify cold solder joints easily this way.

Yup! TDRs are way cool devices and have lots of uses.

se

 

[kwkarth]

Quote:

Originally Posted by Koyaan I. Sqatsi /img/forum/go_quote.gif If you're talking about the one in Stereophile by I believe it was Herve Deletraz, it was a misguided and misleading article. It didn't show that. The line was pinged with a very fast risetime pulse, just as is the case with a TDR. It wasn't pinged with any audio bandwidth signal. You wouldn't be able to get any appreciable reflections or impedance mismatches in the audio band. Not unless your cable was tens of miles long. Hell, cables don't even have a characteristic impedance at audio frequencies. That's why they're evaluated using lumped, rather than distributed parameters. But the reasoning was misguided. I even wrote JA at the time telling him I was surprised that Stereophile would even print such an article. Yup! TDRs are way cool devices and have lots of uses. se

I can't disagree with what you say, but I still thought it was an intriguing article. BTW, aren't MIT cables supposedly making use of this line of thought? I've never had one to play with, but it would be interesting to see which damages the signal least, a plain cable vs a network at the end of a cable. Bet i know which one wins...Hint, The signal flow mainly (better) in the plain...

 

[Shike]

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Originally Posted by kwkarth /img/forum/go_quote.gif Built to "spec?" Who's spec? Your tests?

Built to spec, as in there should be no audible deficiencies for a particular length based on physics.

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Can you produce your instrumentation and lab certifications?

Considering it was a supervised lab I did for fun before changing degrees I'm pretty sure I'd have neither of the above?

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To what resolution did you measure? What was your "margin of error?"

Obviously I don't have this information on hand. Our teacher had over forty years experience and the equipment was brand new freshly calibrated. That's the most I remember besides the end result, because the end result was what it was.

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Where did you obtain information specifying what electrical parameter produced what audible change?

Do you even know what parameter produces what audible change? How is this even relevant to cables measuring the same.

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To how far do you extend this "there is no difference" net? Do you assume because you've "measured" no difference between two cables that there is no difference between any cables?

I believe in law of diminishing returns in forms of audibility. You can make a cable sound different if you want . . . of course many would question if it's built right. We can strip shielding, live next to a radio tower, and make it out of corrosive material. Doesn't mean we should.

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Did you use time domain reflectometry to characterize your cables also, or do you assume those characteristics are out of the audible passband?

We didn't have a TDR on hand, and honestly I doubt we would have bothered for obvious reasons.

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I am curious how you came to adopt such a seemingly simplistic view of your audio world. Did someone else teach you this?

Everyone learns something from someone. Your audio view more or less has been developed by others too.

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There seems to be a lot more wiggle room in their verbiage, in places, than there is in yours, such as phrases they are fond of using, eg. "There are differences between capacitors, but they are not (generally) audible - despite the claims." and frankly there are a myriad of questions that much of their prose generates. They, like many, make blanket pronouncements well beyond the scope of their apparent experience.

If you pick an insufficient capacitor or one not designed for the purpose it will sound different. That's why one has to use a blanket statement, because someone is bound to cite an example where it's done wrong (objectively) and makes a different sound.

 

[Steve Eddy]

Quote:

Originally Posted by kwkarth /img/forum/go_quote.gif I can't disagree with what you say, but I still thought it was an intriguing article.

That's rather what JA's reply to me was. He found it "interesting." I didn't press the issue, but I didn't find much interest in something which took something which was already known and misapplied it to the audio band.

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BTW, aren't MIT cables supposedly making use of this line of thought?

Not that I'm aware of. Bruce's "networks" were typically used ultimately as passive EQ, rather than any attempt to provide a particular termination impedance.

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I've never had one to play with, but it would be interesting to see which damages the signal least, a plain cable vs a network at the end of a cable. Bet i know which one wins...Hint, The signal flow mainly (better) in the plain...

Probably so. It would be easy enough to give it a try. Bruce's patents, which describe the methodology of his filters are readily available online.

se

 

[kwkarth]

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Originally Posted by Shike /img/forum/go_quote.gif Built to spec, as in there should be no audible deficiencies for a particular length based on physics.

That's not a spec


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Originally Posted by Shike /img/forum/go_quote.gif Considering it was a supervised lab I did for fun before changing degrees I'm pretty sure I'd have neither of the above?

Well, then your results don't need to be paid attention to according to your stated criteria.



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Originally Posted by Shike /img/forum/go_quote.gif I don't have this information on hand. Our teacher had over forty years experience and the equipment was brand new freshly calibrated. That's the most I remember besides the end result, because the end result was what it was.

What it was, was unqualified, therefore inadmissible by your standards.



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Originally Posted by Shike /img/forum/go_quote.gif Do you even know what parameter produces what audible change? How is this even relevant to cables measuring the same.

As a matter of fact, yes, I do.



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Originally Posted by Shike /img/forum/go_quote.gif I believe in law of diminishing returns in forms of audibility. You can make a cable sound different if you want . . . of course many would question if it's built right. We can strip shielding, live next to a radio tower, and make it out of corrosive material. Doesn't mean we should.

I don't remember anyone suggesting we do that. Again, what is built right? Who makes the "specs?"

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Originally Posted by Shike /img/forum/go_quote.gif We didn't have a TDR on hand, and honestly I doubt we would have bothered for obvious reasons.

um, ok. Do you believe that a bad/cold solder joint or overly crimped (crushed) cable can affect the sound?

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Originally Posted by Shike /img/forum/go_quote.gif Everyone learns something from someone. Your audio view more or less has been developed by others too.

Absolutely! I've learned and do learn a great deal from others I interact with.

Quote:

Originally Posted by Shike /img/forum/go_quote.gif If you pick an insufficient capacitor or one not designed for the purpose it will sound different. That's why one has to use a blanket statement, because someone is bound to cite an example where it's done wrong (objectively) and makes a different sound.

Hmm, curious, "insufficient" in what way? Who defines "right" and "wrong?"

Thanks!

 

[kwkarth]

Quote:

Originally Posted by Koyaan I. Sqatsi /img/forum/go_quote.gif That's rather what JA's reply to me was. He found it "interesting." I didn't press the issue, but I didn't find much interest in something which took something which was already known and misapplied it to the audio band.

it was food for thought, and remember, even though you and I agree on many things, I am still one of those pesky "believers." I do hear differences in cables, and I'm still looking for a scientific explanation for same.


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Originally Posted by Koyaan I. Sqatsi /img/forum/go_quote.gif that I'm aware of. Bruce's "networks" were typically used ultimately as passive EQ, rather than any attempt to provide a particular termination impedance.

Exactly what I remember reading. What was he trying to EQ "in" or "out?" In my mind, as is probably in yours, the first rule of designing / building a cable is do no harm (to the signal) therefore any EQ network in a cable would be anathema to that principle.

Quote:

Originally Posted by Koyaan I. Sqatsi /img/forum/go_quote.gif Probably so. It would be easy enough to give it a try. Bruce's patents, which describe the methodology of his filters are readily available online.

yup.
k

 

[Steve Eddy]

Quote:

Originally Posted by kwkarth /img/forum/go_quote.gif it was food for thought, and remember, even though you and I agree on many things, I am still one of those pesky "believers." I do hear differences in cables, and I'm still looking for a scientific explanation for same.

Ah, but what if the scientific explanation doesn't comport with your beliefs? Will you reject the science in favor of your beliefs, or will you change your beliefs in favor of the science?

If the former, why attempt to invoke science at all? And if the latter, why hold to a particular belief in the first place?

That's why I'm neither a believer nor a non-believer. I'm an un-believer. I hold no rigid beliefs one way or the other. Makes life much more simple.

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Exactly what I remember reading. What was he trying to EQ "in" or "out?" In my mind, as is probably in yours, the first rule of designing / building a cable is do no harm (to the signal) therefore any EQ network in a cable would be anathema to that principle.

I really don't recall specifically anymore. I only know that it seemed to be little more than a cure in search of a disease.

se

 

[Shike]

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Originally Posted by kwkarth /img/forum/go_quote.gif That's not a spec

It's guidelines for a spec, because different lengths and applications will change the spec no matter what you do.

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Well, then your results don't need to be paid attention to according to your stated criteria.

You mean your stated criteria. No matter what there still is no proof that "properly" (objectively) made cables will show a difference. All I did was actually test it to gain proof for me of the contrary, and at least did some testing that showed something for me.

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What it was, was unqualified, therefore inadmissible by your standards.

I don't believe I ever brought up qualifications?

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As a matter of fact, yes, I do.

Really? Why don't you have proof of why cables sound so different then? Where's the evidence? Please, do tell.

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I don't remember anyone suggesting we do that. Again, what is built right? Who makes the "specs?"

What is built right? Are you honestly this pedantic? Obviously if the cable is made for use in audio, it shouldn't allow for negative impact on the audio band. In other words little to no deviation from the intended signal going from point A to point B.

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um, ok. Do you believe that a bad/cold solder joint or overly crimped (crushed) cable can affect the sound?

Of course, but that's a poorly built or abused cable.

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Hmm, curious, "insufficient" in what way? Who defines "right" and "wrong?"

If it's going to adversely effect the audio band from a reproduction standpoint, many would consider that "insufficient" or "wrong".