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MarkZ said:
Resistance does not significantly rise with frequency. The way I define "significantly", it would have to come somewhere close to the several kilohm input impedance of the amplifier. But it doesn't. It'll add only a couple ohms. No one would call that significant.

Besides, like I said elsewhere, the easiest and cheapest way to combat the skin effect is by increasing wire gauge (thereby increasing surface area), not by implementing special new strand/dielectric properties or cable geometries.
why does it have to be several kilohms to be significant? in the measurements i've seen, some cables had over 20 ohms resistance at 20kHz. besides, we're not just talking about speaker cables but also other cables like interconnects where a difference would be more audibly significant.
 

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cotdt said:
I read this entire thread and didn't notice you mentioning shielding at all, so I had to mention it.

The expensive cables have different RLC values as compared to cheap radio shack cables, so I wouldn't be surprised if people hear differences. if i remember correctly, they have lower L and C, but slightly higher R than cheap cables.
This is where the Fred Davis paper becomes really handy. He did just this experiment by looking at R, L, and C of a handful of cables. One thing you often find is that, due to the typical methods to reduce L and C, you often have a reduction in L but rise in C for some cables, and vice versa for the others. But again, it's important to mention that the Davis paper looked at speaker cables. The reason he looked at those was because speaker cables go in low impedance circuits. R, L, and C in RCA cables is so incredibly low compared to the load impedance that it's insane to even think that differences in R, L, and C could have any impact whatsoever. To be perfectly frank, anyone who thinks that it does clearly has no knowledge of the basics of circuit theory, really making them not equipped to even engage in the debate.

Anyway, I can provide the Davis paper in pdf form to those interested in seeing the data.

The larger debate here is measurements versus hearing. There are those who claim that all cables, all sources, all decent speakers, and all amplifiers sound exactly the same, and they use (flawed) blind tests to prove it, and somehow the results agree with them. Yet to me the difference is like night and day. Usually I can both hear and measure a difference, but not always. In the case of amps and sources, it is not easy to measure since the response is almost always flat even with terrible-sounding equipment, and distortion is also low. Linear and nonlinear distortion entirely influences the sound and nothing else, this is the theory and I'm not disputing that. Nevertheless, with more sophisticated measuring equipment, people find that often there is indeed a measurable difference just like their ears have told them long ago. For example, you can have two speakers both EQed to flat response, and both have distortion below audibility. Let's say one is a magnesium cone, and the other is a sliced paper cone. However, the difference between the two drivers is easy to hear because the two cones have different timbre. This means they have very different local frequency response but you need a very high resolution frequency response measurement, so this is a case where we can't measure it but in theory it's measurable. I think it's similar with other audio things like amps and sources. We hear the difference but the differences are not easy to measure, so this is why I put hearing over measurements.
What makes you think that distortion and frequency response can't be measured with even the cheapest instrumentation? Even my cheap sound card has far better resolution than any human's auditory system.
 
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Discussion Starter #64
Check my very first post in this thread, you'll see shielding mentioned. And it's not the only post.

Speakers are more complicated to measure than electronics, for a couple reasons :

- There is the added "dimension" (actually, 3 of them) of space.
- They distort more than just about any piece of electronics in the chain ... at levels significantly above hearing thresholds ... so comprehensive measurements of distortion are also required.

Doesn't mean that science doesn't have the tools necessary to measure what loudspeakers do to the air between them and your ears ;)

RCA cable resistance will matter MUCH, MUCH less than loudspeaker cable resistance, because the load (amplifier input, on the order of 10kohms) is about three orders of magnitude higher than a typical loudspeaker.

Double-blind testing of cables has demonstrated what science and logic dictate ... there is no audible difference in cables that can't be attributed to what logic and valid engineering demonstrate.
 

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cotdt said:
why does it have to be several kilohms to be significant?
Because that's what the load impedance is. Do you know what a voltage divider is?

in the measurements i've seen, some cables had over 20 ohms resistance at 20kHz.
Yikes! Which cables were those??

Even so, 20 ohms with a 5kohm input impedance amounts to only about .01dB.

besides, we're not just talking about speaker cables but also other cables like interconnects where a difference would be more audibly significant.
Actually, quite the opposite is true. I thought you were talking about interconnects at first, hence my use of 5kohm as a load impedance value. With speaker cables, the difference is more realizable since it's a lower impedance circuit. But even with that, resistance DIFFERENCES in cables are insignificant. And the best way to combat them (better than all other elaborate methods) is to just increase wire gauge.
 
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actually cotdt ... i mentioned noise shielding twice in my very first post in this thread ... did you even read it?
 

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There is nothing about audio signal transfer over cables that is not understood by electrical theory. There is no "mysterious" aspect of low frequency current flow through conductors, that cable salesmen understand ... but electrical engineers do not.

If what you heard is indeed real, it is absolutely explainable by the electrical laws described in this thread.

Why do you believe otherwise? Even if what you heard is real ... and I'm not convinced one way or the other ... why are you convinced it is somehow "beyond" electrical theory to explain it?

Were all RLC, shielding, and metallurgy properties of the cables comprehended? That's the only way to be convinced that real sonic differences must be "beyond" these properties.

Even if I grant that what you heard is real ... why be so convinced that electrical engineering can't explain what you heard?
 
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Discussion Starter #70 (Edited)
allow me to elaborate AVI ... i'm really not trying to pick on you :)

Let's say that two cables to be compared are inserted into a system. The frequency responses ... including magnitude and phase over the audio band ... are measured in each instance. The measured responses are found to be virtually identical ... meaning, less than 0.1dB/1 degree at any frequency measured. A double-blind test is administered, where neither test administrator nor subject know which cable is being tested. No other variables are changed during the test ... including warm-up or power line fluctuations of electronics, break-in of speakers, building AC system switching on during one cable but not the other (possibly causing electrical or acoustical noise as well as power line fluctuations), etc. {Sound crazy? Sound overly anal? Welcome to the exacting world of the scientific method :)}

Sure enough ... a statistically meaningful difference is recorded, that can not be explained by random chance.

In this case, one may readily conclude that RLC aspects of cables ... which give rise to measurable cable frequency responses, as described in this thread ... do not explain all there is to know about "cable sonics." In other words, ONLY once all known effects are eliminated, may one conclude that some mysterious "unknown" is the cause.
 

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AVI said:
Here's what I know for POSITIVE ....

http://www.diymobileaudio.com/forum/showthread.php?t=7513

Electrical measurements can NOT explain results like this ... Logic and specs go right out the window ;)
Why can't logic and specs explain that, because you don't like them too? Werewolf isn't saying that there is no difference in cables, or that you didn't hear what you heard, he's saying if you DID hear it, the differences can be measured, and explained, through 3 different "specs" of the cable in question. He's saying if there were F/R anamolies present, it was due to the length, resistance or capaticance change from cable to cable Not due to the cable geometry or other "high tech cable breakthrough". If spending $75 a foot for cable makes you feel better about yourself and your system, go ahead. If that's what it takes to allow you to really listen to your music and enjoy it then you may as well. While it may not make an actual difference, over a cheaper cable that's properly shielded with simlilar LRC values, if it gives you the incintive to listen for the low level details then why not? The human minds funny like that, it really can make 2 things that are EXACTLY the same, be percieved as different. Peace of minds worth something too, and if you really believe a more expensive cable has something to offer, you may never be pleased with anything less, regardless of how it actually sounds vs a cheaper cable. However, not everyone has enough money to spend on hyper expensive cables, so for them, knowing that a less expesive cables with similar RLC values will sound the same, geometry be damned, is important. There is one more thing I like to add, hopefully avi does read this, I think he may appreciate it. I believe I've used this quote before in a similar theread, and I think I'll use it again, this thread is asking for it even more.

"It is sometimes said that scientists are unromantic, that their passion to figure out robs the world of beauty and mystery. But is it not stirring to understand how the world actually works — that white light is made of colors, that color is the way we perceive the wavelengths of light, that transparent air reflects light, that in so doing it discriminates among the waves, and that the sky is blue for the same reason that the sunset is red? It does no harm to the romance of the sunset to know a little bit about it."
 

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Ok Guys ... I misunderstood what your previous posts in this thread were driving at. That's my mistake.
I truly wasn't trying to make a counterpoint for argument's sake.
Werewolf , I believed you were driving at the point that RLC is the only thing that can make cables sound different , and that for the most part different cables would NOT have enough difference in RLC to actually hear ?
You can believe this : I'm a part of this forum to further my knowledge of all things audio ! Not to stir things up.
I knew that my experiences with blind testing were real , and thought your scientific points were saying that they could not actually be real.
My bad for mis-reading / mis-interpreting what you were saying.


Now that I understand better , that leads me to ask this :
What exactly makes it so that RLC can be so very different between cables , that actually does allow a person to hear differences sometimes ?

Is this where manufacturers simply get lost .... trying to explain the differences in simple RLC with " snake-oil " ? If so , why don't they just quote the differences is THEIR particular RLC make-up ?
 

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T3mpest said:
Why can't logic and specs explain that, because you don't like them too? Werewolf isn't saying that there is no difference in cables, or that you didn't hear what you heard, he's saying if you DID hear it, the differences can be measured, and explained, through 3 different "specs" of the cable in question. He's saying if there were F/R anamolies present, it was due to the length, resistance or capaticance change from cable to cable Not due to the cable geometry or other "high tech cable breakthrough". If spending $75 a foot for cable makes you feel better about yourself and your system, go ahead. If that's what it takes to allow you to really listen to your music and enjoy it then you may as well. While it may not make an actual difference, over a cheaper cable that's properly shielded with simlilar LRC values, if it gives you the incintive to listen for the low level details then why not? The human minds funny like that, it really can make 2 things that are EXACTLY the same, be percieved as different. Peace of minds worth something too, and if you really believe a more expensive cable has something to offer, you may never be pleased with anything less, regardless of how it actually sounds vs a cheaper cable. However, not everyone has enough money to spend on hyper expensive cables, so for them, knowing that a less expesive cables with similar RLC values will sound the same, geometry be damned, is important. There is one more thing I like to add, hopefully avi does read this, I think he may appreciate it. I believe I've used this quote before in a similar theread, and I think I'll use it again, this thread is asking for it even more.

"It is sometimes said that scientists are unromantic, that their passion to figure out robs the world of beauty and mystery. But is it not stirring to understand how the world actually works — that white light is made of colors, that color is the way we perceive the wavelengths of light, that transparent air reflects light, that in so doing it discriminates among the waves, and that the sky is blue for the same reason that the sunset is red? It does no harm to the romance of the sunset to know a little bit about it."
Thank you for the tasteful and helpful post.
Please understand , that if i seem defensive , it is due to previous discussions over the years with scientists I have had. MANY of these insisted my experiences with my in-depth blind testing was pure BS , and that under NO circumstances can ANY human EVER hear a difference with different cables ...... This was basically like calling me a fool and a liar .... THAT will tend to make a person defensive , especially when he only has his personal experience to draw from , and not a 170 IQ ;)
 

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Cool thread. Thanks Mark Z and Werewolf for the scientific breakdown. Always "felt" that expensive cables did not "improve" the sound, and now I understand the science behind that feeling. I have always spent a little extra money for quality connects and shielding, but never anything crazy. Same reason I never spend a ton of money on speaker cable. Rather have something more important .. like more watts ;)
 

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AVI said:
MANY of these insisted my experiences with my in-depth blind testing was pure BS
They may very well be. You didn't describe your testing paradigm in detail. "Blind testing" is not exactly trivial...

and that under NO circumstances can ANY human EVER hear a difference with different cables ...... This was basically like calling me a fool and a liar .... THAT will tend to make a person defensive , especially when he only has his personal experience to draw from , and not a 170 IQ ;)
No one is calling anyone a fool or a liar. I think everyone is being completely forthcoming in this discussion.
 

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AVI said:
MANY of these insisted my experiences with my in-depth blind testing was pure BS , and that under NO circumstances can ANY human EVER hear a difference with different cables ...... This was basically like calling me a fool and a liar
I think the only time people would consider a person a fool or a liar is if they based the differences in SQ of cables based on the fact that they have Teflon coated Egyptian cotton dielectric wrapped around buckyball carbon nanotubes filled with ferofluid that has been cryogenicly frozen in a anechoic chamber, twice. And they believe the cables sound better from this even though they measure the same as a $1 radio shack cable.

The way I pretty much sum this all up is if the cables measure the same in respect to RCL, they will sound the same. Price not a factor ;)
 

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AVI said:
Thank you for the tasteful and helpful post.
Please understand , that if i seem defensive , it is due to previous discussions over the years with scientists I have had. MANY of these insisted my experiences with my in-depth blind testing was pure BS , and that under NO circumstances can ANY human EVER hear a difference with different cables ...... This was basically like calling me a fool and a liar .... THAT will tend to make a person defensive , especially when he only has his personal experience to draw from , and not a 170 IQ ;)
No problem, it happens. Anyway, most manufactures claim other things matter to help boost sales. If the average consumer was a engineer, they'd know that cable geometry doesn't matter. And that no 100 page tech paper was going to change the VERY simple laws that govern electicity flowing through a wire. They'd know that honestly, musical singals aren't that complex, and don't require any hyper special cable treatments to be sent across a cable accuractely. The average consumer, however, isn't an engineer. If they are paying 20x the price of a el cheapo cable, they need justification. If that means the cable company pays actual engineers lots of money to use "pseudo science" to create a "superior" cable, then so be it. If they can minimize lower the "skin effect" from 1000x below the threshold of human hearing to 1000000x below the threshold, then so be it. They have to justify the price of the cable to an audiophile, and if that means making stuff up, then so be it. Using actual electrical theory makes cables too simple, just by measuring 3 specs of a wire, any decently designed wire can be compared vs one another easily, it's too hard to raise the price that much when only 3 little numbers change each time.
 
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Discussion Starter #79
A quick summary of my views on audio cables, for what it's worth ...

If someone says, "I can hear a difference in cables." I find that statement very un-interesting.

HOWEVER, if someone states the following :

"After a well-controlled test where all other possible variables were eliminated, a statistically significant result demonstrated, logically and conclusively, that differences in cables were audible. Furthermore, the RLC properties (as well as contact metallurgy and noise shielding) were measured, and the differences were found to be below the threshold of human hearing."

Now THAT would be very interesting indeed!

But I have yet to hear that statement ...
 
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