Comment 15 for bug 1481170

I think we're converging on a good design. Maybe we can have a per-effect boolean flag that determines how it is cut -- something like a reverb can be "until mostly silent for 1 second" and a distort can be "absolute fadeout period".

I'm *extremely* reluctant to add yet another preference for this. Let's start by hardcoding something simple, like 4 beats / 3 seconds, and test. If the default fadeout time is not desirable, a user can just use the dry/wet knob instead. For now let's do this without any new preferences.