Sonic difference 1.0m vs 1.5m digital cable

What about digital cables with XLR termination?
The article from positive-feedback refers only to RCA cables. Does it mean that with AES/EBU digital cables the length does not matter?
Thanks

Thanks Sean for the explanation and let us know your test results if you are proceeding with this. My sense is with most i/c (including digital) they will not sound the same at different lengths but generally longer means trade offs with something else for eg: resistance but will they sound better with this trade off?

Digital is an RF signal and changing cable length with an RF signal WILL alter the response of the circuit. This is true UNLESS the input, output and cable impedance are all identical. Anybody that tells you differently lacks experience in this specific field, regardless of the cost of their cabling or their past credentials.

Having said that, the wavelength at these frequencies is VERY long. I don't know how much of a difference such a short difference in cable length would alter actual impedances in a less than optimally matched sytem, but it has been shown that it will alter the return time of the reflections that occur. Depending on the stability of the output stage in the transport, it might be important or it might be moot.

If someone REALLY wants to know, i can do some impromptu testing and provide "less than set in stone" type results using a digital analyzer and a make-shift circuit. I can take some 75 ohm coaxial stubs of 1 and 1.5 meter length and measure the feedpoint impedance when shunted. Only problem is that all of my test gear is set up for a 50 ohm nominal impedance, so the results may not be exactly perfect. It would give us an idea as to whether or not there was a sizable shift in loading conditions though.

With all of that in mind, if one terminates the cable with the appropriate value resistor at the input of the DAC, most of this becomes moot. The value of the resistor used would vary depending on the actual components and cable completing the circuit. The first company that i know of to take this approach was Tara Labs and that was so long ago that Tara didn't even remember doing it. Sean
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I bougth a used PAD Digital cable and it was 1,5 m. Way longer that I need. I was told that this length was the best.
I asked this Q to Jim Aud of Pad and also to the owner of Sterovox and both answered that the length has no effect on the sound.

Thanks for the responses so far and hence after reading what has been discussed in AA and here I 'm not convinced this will make a difference subjectively, though the techincal explanation makes sense to me. I guess it is system dependent and as some might say YMMV.....

There's been a lot of discussion about optimum digital cable length on AA's cable asylum, with adherents favoring l.5 meters, 7.5 feet and -- lately -- as short as humanly possible. I'm currently running a 6-inch link between a moded Toshiba 3950 and an Ack dAck! and it seems to sound a LITTLE better than the longer ones I've tried, but I could well be kidding myself. Dave

digital cable with passive preamp?????

I forgot to mention that the difference might be audible to a select few if you are using a passive preamp. Even then I have serious doubts.

Some would argue that the LONGER digital cable actually sounds better. At least I remember that argument having been made before.

Would take some mighty golden ears, IMO. I've never heard a difference of a half meter of IC or speakerwire. I suppose if it were not well shielded that the longer length would make it a bit more prone to picking up hum from other components and power lines.