Gudday all. Here's Magnum Opus. As Jörg Sprave would say, "Let me show you it's features, ha ha ha".
It's a Boneyard on the vero layout from Tagboard, and as can be hit and miss with this thing (even on vero), I was lucky enough not to have any squeal so it became a base for this build. It was originally inspired by a video of the Keeley El Ray Dorado that has Bat46 (41?) as a second clipping option - but when you switch there's a volume drop so it's not something you set up on the fly. That bugs me, so the original intention was just to do a gain/volume/diodes on a footswitch. And then I got silly.
While I like the Boneyard/plexitone, I've always wanted more gain/saturation from it so I started looking at a lot of my fav drives. The Crunchbox has hard clippers to ground, the Zendrive has a pretty elaborate set of clippers, the Valvestates have green/red leds in a back to back pair going to ground. While I hate the OCD, I decided to use its' 2n7000s, and drives like the @T have multiple clippers to ground.
I removed the 68n tone cap/tone pot and replaced it with a bandaxall eq from Parasit.
So, it has:
OD1 - Symmetrical green LEDs (sounds great), no diodes, Zendrive clipping. For some reason I couldn't get the Bats to sound good)
OD2 Low - Symmetrical red LEDs, no diodes, Zendrive clipping
OD2 High - Back to back red LEDs, no diodes, asymmetrical 1n4148s
Hard clipping - back to back 2n7000, red LEDs, Bat 46(41?)
Hard Trim - just a pot to control the amount of hard clipping. Needs replacing as it's all bunched. Maybe a different taper or size - edit, the 100kB has been replaced with a 10kA. It's better, but it still seems to be either "flat out" or "not at all" with a pretty small area for adjustment. Maybe something like the Turnabout's 10kC would be better.
Body - selects between 1uf, 1.4uf, 2uf as I felt 1u (the newer plexitone value was a bit low but 2.2 could be a bit high)
A bandaxall eq using Parasit's layout.
And... a master volume to finish it all off...
EDIT: I wasn't getting unity when some of the hard clipping options was engaged with the other clipping in some cases. LEDs were generally fine, but the other diodes took too much out of it. I was going to add an external boost but then I had a lightbulb moment, remembering that the Boneyard/Plexitone had a switchable boost, so I removed a jumper and soldered a 330k across instead, leaving the boost engaged. This gives me enough level for unity+ in all the options, meaning that the soft clippers only channels needed to have their volumes brought down, which is easy enough. Problem solved.
