I always seem to be on a quest for more/better distortion! I’ve built a few distortions, but I still wasn’t happy with the situation. The Plague Bearer is killer, but it’s quite a particular sound and not suitable as a “general” distortion. The Antumbra DIST sounds great, but the output volume is far too low. The fuzz I built is great, but there’s very little control. The Rat clone is great, but I need more! Finally the distortion in my Mutant Bassdrum is pretty permanently in use for the Bassdrum itself.
The first thing I decided to do was mod the DIST. By cutting the trace between R8 and the input on pot 3 and inserting an op amp (TL071), along with a couple of filter/bypass caps and a couple of resistors, I was able to dramatically increase the output volume.
I just glued the IC socket to the back of the board and wired it all up. Looks kludgy as hell, but it works!
The second thing I did was to pick up a failed RYO Optodist build from Johnny Sideways. He’d burned out a couple of resistors and given up on it, so I attempted a repair. First off, I reflowed everything (some of the soldering was a little questionable as it was one of Johnny’s first builds) and gave the board a thorough clean with IPA. I suspected something must have been shorting, and it all looked good after a reflow so I replaced the burned out resistors and powered it up…. and filled the room with magic smoke!
Obviously something still wasn’t right and I’d need some more resistors! The first thing I checked was that the op amps were correctly oriented and what do you know, that was exactly the issue! Flipped them round and replaced the resistors again, along with the electrolytics as one of them was looking a bit ropey, and the protection diodes for good measure.
Tidied it all up and gave it a test. All working perfectly now. I’ll probably replace the somewhat melted trimmer at some point, but it works fine, so maybe I won’t!
I did, of course refill the magic smoke afterwards as it’s essential for the correct operation of any module 😉