Sort of off-topic, except that i want to do it on linux and it does have to do with audio :) I've been wanting to tinker a bit with analog audio circuit design. I've built a few boxes from schematics but I've never actually designed a circuit. What I'd REALLY like is some GUI software in which I can construct a circuit diagram and then feed in a test audio signal and through some DSP magic, hear (more or less) what the result would sound like before I start using my big clunky hands to ruin physical objects :) Does such a thing exist? Or some combination of software that would do the above? I've been looking at some SPICE resources online but I can't tell if you can feed an arbitrary digitized audio signal into a SPICE simulation. -- Paul Winkler http://www.slinkp.com Look! Up in the sky! It's PURPLE KABUKI WARRIOR BOOMERANG! (random hero from isometric.spaceninja.com)