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Old 11th August 2014, 03:00 PM   #51
DF96 is offline DF96  England
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Of course cables can make a difference, but only if the cables or the equipment are unusually badly designed.

A really bad cable will allow in interference or even hum. This is how some audiophile cables work (that is, the ones which actually make a difference).

A really poor source will have high output impedance, and this will react with the cable capacitance to produce an HF rolloff - 'smooth' sound. If the cable has very high capacitance and the source has very high output impedance then there is a small chance that dielectric non-linearity could introduce a little HF distortion (especially if the cable is deliberately 'poled' with a battery) or dielectric DA could add a tiny bass or subsonic boost.

This is why competent cables attached to competent equipment all sound the same i.e. no sound at all.
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Old 14th August 2014, 04:36 AM   #52
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Now look, we know that's completely ridiculous because of so much anecdotal evidence to the contrary.

I am, however, always willing to change my beliefs if the evidence is there. Thus, I did some more testing, constructing a small switch board so I could instantly and silently connect and disconnect the "bad" cable. I listened with music, tones and noise signals. I listened with speakers and headphones. Unless I did something really wrong, always possible, the results were crystal clear:

There was no detectable difference between any cables I compared. None, zero, zip and nada.

The brain and listening biases are an evil thing, but I've changed my page to reflect the new results.

Alas, this is the same thing that's happened when I looked into the differences between different metallic conductors and several other things. The closer one looks into the supposed differences, the further they recede, until all that remains is the grin, which slowly fades from view as well.

In general, we can measure far better than we can hear.
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Old 14th August 2014, 05:42 AM   #53
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"Thus, I did some more testing, constructing a small switch board so I could instantly and silently ///"

Just so I follow this correctly, you performed a sighted A/B switch of two cables right? The switching time is instantaneous, something like 50 ms, is that right?
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Old 14th August 2014, 11:04 AM   #54
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Quote:
Originally Posted by Conrad Hoffman View Post
Now look, we know that's completely ridiculous because of so much anecdotal evidence to the contrary.


It's a pity that so many people actually believe that. The rationalizations for why their beliefs aren't verified when actually tested can range from entertaining to remarkably lame and dreary.
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Old 14th August 2014, 02:41 PM   #55
DF96 is offline DF96  England
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Quote:
Originally Posted by Conrad Hoffman
There was no detectable difference between any cables I compared. None, zero, zip and nada.
Quote:
Alas, this is the same thing that's happened when I looked into the differences between different metallic conductors and several other things. The closer one looks into the supposed differences, the further they recede, until all that remains is the grin, which slowly fades from view as well.
Surely you are not expecting us to believe that naive circuit theory and materials science, as taught to millions of EEs down the years, is fully applicable to audio connections?
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Old 14th August 2014, 03:38 PM   #56
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The Audiophile will say that it is your switching circuit that is to blame....
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Old 14th August 2014, 03:39 PM   #57
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Quote:
Originally Posted by udok View Post
Hello again,

I modeled your measurements with lossy cables in LTSpice.

The result - after playing 5 minutes with the values is not perfect,
but it looks very similar to your bad cables (Picture is attached).
That's a good shot, IMO. I tried something as well and I confirm your results.
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