Hey, it is all analogue.
It is not a question of loss. It is a question of reflections. Real long story short......
We did a lot of research (and yes, it was by nature "analog") back in the early 90s on how much reflections that you could tolerate on an SPDIF interface, and not muck up the sound.
The answer we came up with is around -30 dB. Below that point, things all sounded about the same. (Translation: cables did not sound all that much different if all the impedances could be that tightly controlled.) In layman's terms: the refection can only be 3% of the value of the signal.
Our latest "not-so-top-secret" project has an output return loss of -38 dB. Around 1.25%.
Our cables usually run in the -32 to -34 dB range.
What is the output return loss of a typical RCA connector? They range in the 25-30 ohm range. That gives you a return loss in the -10 dB range. Which is what we have measured on many occasion for the skeptics.
Help any???
(Pssst........I can sell you a really good isolated BNC at cost.)
Pat
