Here’s a good, subtle sounding compressor. It uses a LDR and LED to control the limiting done by the effect. You can go the home-brew route and put a LDR and LED in some shrink tubing or there should be enough space to use a VTL5C2 or a NSL-32 photocoupler. Diodes I’ve listed as 1N34s but any germanium diodes should work.
