2 & 4 was a complete makeover for me.
I don't do the drone/ambient style at all, so being able to dial the effect in subtly made it work a lot better for rock'n'roll. IMHO, with that setup, it rivals any digital 'tape delay' I've heard.
So I was fumbling around with using an opamp servo to bias JFETs and Chuck followed with a killer servo design for a Fuzz Face-style Germanium fuzz.
In short, it's the absolute BALLS. Easily among the favorite fuzz boxes I've ever built - or played, for that matter.
You can see the schematic and...