Hey, muksys, nice knob “mod”! What part are those knobs? Do they just slip on, or did you need to glue/set screw in place?
They’re Rogan knobs made specifically for older Make Noise modules that have the same type of pots as the Werkstatt (knurled shafts). I got them from ctrl-mod.com but it looks like they are currently out of stock. They fit on perfectly. No screw or glue needed.
has anybody here tried to add a highpass output to their werkstatt filter?
usually, with this type of filter you get a highpass signal by mixing the lowpass output with an inverted version of the input signal. so all you would need to do would be add some kind of basic inverter+mixer circuit. might be worth a try.
i’d love to have one of these around to experiment with myself. but they are not available here in europe, and importing one from the u.s. would be too expensive, what with shipping cost and import tax. the current usd/eur exchange rate isn’t helping, either. 
also, has anybody done anything with that unused ota in u2 (lm13700; jmp9, 18, 27, 36, 45) yet?
This is probably better suited here, so I’m gonna double post…
Here’s the variable waveshape mod schematic:
It’s a bit tricky to get in. After removing the switch I was able to solder the pot in the holes (with the wiper bent up). Had to bend the pins back but it fits. The Saw trace between the 2 switch pins has to be cut and Square trace has to be cut between the switch and the TP (cant remember off hand which TB it is). Then I soldered a wire to the Square TP and the unused Saw pad from where the switch used to be. Finally the Mix wires to one of the old switch center pads. here is a vid of the mod in action
…and here’s the PCB with all of the additional mods.
Right now I’ve been hand soldering em but I may look into getting them made and sell kits if enough people are interested.
Very nice! If I didn’t already have my spaghetti mess of a Werkstatt I’d be first in line for a kit. I really like how you cleanly incorporated the MiniCV board. There are a lot of input and output pads. Do all of those connect up to pads on the Werkstatt?
Thanks! Mine doesn’t have this nice PCB. It’s basically a working canvas. Any mod idea gets tested on it first, so there’s lots of perf boards and spaghetti.
The bottom half of the PCB are 8 buffered outputs. VCO Saw & Square, LFO Tri & Square, KB, EG, Gate & Trig. They all get wired to 4 TRS jacks. The KB Out goes through a trimmer first to scale it to 1v/oct. The top half has a Glide circuit, a mixer (to control the VCO and External Audio IN) and the Gate Buffer.