BlackDeath WAHWAH V847

This is the BlackDeath WAHWAH!

It’s a Kosmo-ified version of the classic V847 wah pedal with a few upgrades - Eurorack/Kosmo style power and diode protection, external CV control, a Q/tone-control knob, an attenuator, an indicator LED, an internal LFO for ‘autowah’, and a switch to switch between manual and LFO/CV.

There are some unique features in this design. It uses two vactrols, which can be purchased or DIY’d, and it uses a part called a resonator which gives it some of the distinctive ‘wah’ sound, which I’ve never seen them used in a synth module before. Trim pots for calibrating the internal LFO are included with touch points for easy calibration.

There are few small mistakes on the v0.1 board, but nothing fatal, just a diode that needs to be replaced with a jumper, and two pots that need the 1 and 3 legs crossed if you don’t like having ‘backwards’ pots. If there’s enough interest, I’ll make sure that these small mistakes are corrected in the next version of the board.

There are two components on the board that I’ve labeled to use sockets if you like, as changing the values will somewhat change the character of the wah based on what you need, giving it either more throat or more sizzle, so you can play around with until you find the values you like, or just use the ones provided, which are the values I ended up using.

Patch wise, I found it sounds really good with a distortion before it, or after it like Jimi did, or clean with some house/disco chords, or with a low bassline and the auto wah on to give it some motion and funk. Or, you can run a clean signal through a mult, then patch one into the wah and another directly into the mixer to combine a really low clean signal with a high wubby wah to create a really thick sound. This is a pretty unique module that you should be able to have a lot of fun with.

I recorded a bunch of demos but Audacity crashed and this is all I was left with, but you get the idea: Vocaroo | Online voice recorder

This was made in collaboration with my dad, a mad-synth-scientist who interestingly enough independently invented Kosmo (sort of) on his own many years ago. All of his modules are made from recycled bits, which is where this project came from as we wanted to find a use for some salvaged resonators.

Here is is for scale in his monster:

If anybody is interested, I’ve got 3 available, and I can whip up a few more with a v0.2 board if there’s any more interest after that. If you’re interested, send me a DM! Crazy that less than a year ago I was buying my first soldering iron and getting started with all of this, now I’m getting boards and panels manufactured! Huge thanks to @lookmumnocomputer @analogoutput @Dud and everybody else here whose ever given me advice on electronics and kicad!


ps I’ve got some spare resonators so if you if you order a set I can throw those in too!


I have a feeling shipping from Norway to the US would not be that cost effective… do you have Gerbers online?

1 Like

These are actually in Pennsylvania, USA. :slight_smile: We’re a global operation.

(Hence the goose and the name… if you know, you know… ;))


Good work :slight_smile:

I think it may be cool and interesting to add the schem you used in this thread

looking well good!! do the jacks connect via connectors right?? Nice :smiley:

I think we need to petition Alpha to start manufacturing ‘backwards’ pots with a flipped pinout.

I might have a use for a PCB set, but I need to finish some of my own projects first.

(yes the long awaited VCDO is almost ready, Tayda should arrive next week :smiley: )


Oof for backwards pots. Lemme get a set when you fix the 1 and 3 legs. Great module!

-Fumu / Esopus