Was just poking around eBay today and ended up bidding on and winning one of these ($3.59, free shipping from China!):
This might be the easiest, simplest, and least expensive solution for getting high quality audio out on my digital Theremin. Generate SPDIF in the FPGA, run it and 5V power over to this box, and it's game over. Too bad it doesn't have a headphone output, though line level can often drive headphones.
Makes a great deal of sense! - Digital Theremin with digital (optical / SPDIF or whatever) output .. Supply a DAC to those who want one, studios etc often have desks with digital input... No risk of HF on analogue audio outputs, no ground loop problems particularly if optical.
And no real problem for those who want analogue audio from their theremin - provided you leave enough space in the box to fit one of these if required!
$3.59 inclusive! Couldn't buy the box and connectors for that! - Even the $9 "buy now" price is ok, and would probably drop to $5 if you bought 10+
Dewster you stole these. I get mine from Amazon for ~$20 a set. I have a couple of tube theremins that I use them exclusively to give electrical isolation through a Toslink cable to the follow-up theremin equipment. They also give me a predictable theremin output load for the best audio results. I am learning.