This question came in from CE Pro reader Scott Hetzel of Pro Circuit AV in California. Can anyone help him out?
“Some techs think its OK to send analog line level audio on digital coax. Is there signal degradation in doing so? Will the audio signal suffer doing this? Is this acceptable? I was taught that it is not the right way of doing this type connection. I would love to get some engineering feedback.”
Yes, many pre-made interconnects that you purchase are of coaxial design as well. But, it is very important to use “digital coax” or “serial coax” for this purpose because you need a coax with a solid bare copper (BC) center conductor and a 95% tinned copper braid for proper signal. It is a bit more expensive than Cable TV coax, but pro installers have been using this type of coax for custom interconnects for years.
Note that standard CATV coax should never be used which is made of Copper-clad steel (CCS) center conductor and a 40 or 60% aluminum braid because it offers poor resistance for the audio signal.