Regarding Doug's finding that a longer XLR cable that was not designed for digital applications outperformed a shorter RCA digital cable, that is not at all implausible or surprising.
For one thing, it can often be expected that a modestly longer cable will outperform a shorter one in a digital application, depending on a number of system-dependent variables. For the explanation, see this paper by Steve Nugent of Empirical Audio ("Audioengr" at Audiogon). While the paper discusses S/PDIF, similar considerations can be applicable to AES/EBU, although the specific numbers may be different. None of this is applicable to the much lower frequencies of analog audio signals, however.
Also, of course, a comparison between an unbalanced interface and a balanced interface introduces many variables into the mix besides the intrinsic differences between the cables. In digital applications those would include differences in signal characteristics such as risetimes and falltimes, which are directly relevant to jitter; the fact that different interface circuits are being used in the two components; and differences in susceptibility to ground loop effects and pickup of low level noise, both of which can affect jitter.
Regards,
-- Al
For one thing, it can often be expected that a modestly longer cable will outperform a shorter one in a digital application, depending on a number of system-dependent variables. For the explanation, see this paper by Steve Nugent of Empirical Audio ("Audioengr" at Audiogon). While the paper discusses S/PDIF, similar considerations can be applicable to AES/EBU, although the specific numbers may be different. None of this is applicable to the much lower frequencies of analog audio signals, however.
Also, of course, a comparison between an unbalanced interface and a balanced interface introduces many variables into the mix besides the intrinsic differences between the cables. In digital applications those would include differences in signal characteristics such as risetimes and falltimes, which are directly relevant to jitter; the fact that different interface circuits are being used in the two components; and differences in susceptibility to ground loop effects and pickup of low level noise, both of which can affect jitter.
Regards,
-- Al