Here's a terrific all tranny adsr to go with the all tranny vco. It's based on the OB SEM eg. I added a diode or two to get release and reset so it gates properly, but it's basically the same circuit. Just what I needed. That all-transistor synth is shaping (pun intended) right up...;-) http://www.xavax.com/efm/cbook/pics/eg4-sd.gif Tom