max length of toslink or coaxial digital cable without signal degradation?


I hope this is a fairly straight-forward question and doesn't involve too much subjective opinion.

I have an Oppo 203 in my video stack, quite separate from my audio stack.  If I were to use the Oppo as a transport for a (hypothetical) DAC (sitting in the audio rack), I'd need perhaps an 8' cable to connect them.

Would that distance lead to signal degradation?  Is one transmission mode superior to the other for these kinds of lengths?

128x128twoleftears
Optical works great over long distances. What matters is the jitter rejection capability of what you put at the other end.
Correct me if I am wrong but the Oppo-203 has 2 HDMI outputs, one video and the other for audio only. If you use a 3-5m FIBBR HDMI cable you should get perfect sound. Otherwise you can use a XLR cable to the DAC. Optic is also great as Shadorne says though throughput is limited to 24/96.
In general coax should be better. Toslink has slow transitions that can convert system noise into jitter but doesn't have reflections, doesn't make ground loops and is not sensitive to ambient electrical noise. All comes to jitter that converts to noise. There is no way you can measure  anything so the best way is to try.  Perhaps you can borrow cables from local stereo store.