Audio Cable - Different Purpose
In the absence of decent RCA audio cables to connect a device (e.g. CD player) to an amp, could you use digital coax cables? If so what effect on the quality of the signal is likely?
A real coaxial digital audio cable is a 75 ohm cable (the same as a video cable). It will work for audio but is not optimal. Better audio cables are constructed with a twisted pair (for signal) and a separate shield which does not carry signal. This keeps RF out of the signal and is ofter a higher gauge so that there is less signal loss. Audio inputs vary but are never as low as 75ohm in impedance. They could be 600 to 50K ohms.
The Digital Coax is already shielded......
" A digital coaxial cable offers 75-ohm impedance and a wider frequency bandwidth than the thinner, unshielded RCA cable. If you do connect a standard RCA audio cable, you'll find that you start to lose the signal over long distances, due to the lack of shielding. That lack of signal typically manifests itself in the form of stuttering audio—you're not getting all the digital bits on a consistent basis. You may also notice interference from other electrical devices, including electric lights. The longer the cable run, the worse the signal loss; you may not notice it with short cables (three foot or so).
A single digital coaxial cable carries all available audio channels. You only need a single cable to carry right and left stereo signals, or the 5.1-channel surround sound signals"