Can I use any phono cable for S/PDIF signals?
Many people do, and get away with it, but it really isn’t a very good idea, as you can end up with clicks and glitches that seem to have no apparent cause. At the high frequencies needed to carry digital signals, cable impedance has a significant effect on the shape of the waveform being transmitted, and S/PDIF signals ideally need to be fed via a 75(omega) cable designed specifically for digital data use. If the cable and terminating impedance aren’t correct, energy is reflected back down the cable, which has the effect of degrading the shape of the digital pulses. Poor quality connectors can also compromise the performance, so this is one instance where even the accomplished solderer of cables might be better off buying a ready-made cable of the right length. At longer cable lengths, it becomes even more important to choose a high quality digital cable and, as a rule, cable runs should be kept as short as is practical. AES-EBU signals are more tolerant, though special cable (in this
