Compressor Pedal

Graphics inspired by Audulus. I was originally going to try to cram this into a 1590A box, but there were so many wires and I decided to include all five knobs: Volume, Threshold, Ratio, Attack and Release. So I put it in a 1590B. This also made room for a bigger LED.

I enjoyed making this and getting a bit of a sense on how electricity gets turned into a control voltage, and how components charge and discharge for attack and release. Credit to the Valve Wizard for his design. I decided to also do some recommended mods to the capacitors so it will work well with my bass, as well as including a treble boost. The intent was not only to get some punch and sustain out of the homemade acoustic instruments, but also to even out the amplitude of the notes when recording audio in. Sometimes when you play a bassline, different strings are relatively more quiet or more loud, so I built this compressor to bring the discrepancies together.


Wow! really cool! I’m impressed with how clean the graphics turned out.

That is still basically how triangles and sawtooth waveforms are made in analog oscillators. The rest of the waveforms are derivative to the simple waveform at the oscillator’s core.

Do you have much ambition with the diy builds? There are lots of great module kits.

1 Like

Well, this winter I built the compressor and a russian fuzz pedal. It was a bit of work because both were taken from a schematic and the board layout for one had to be drawn in CAD while the other was done with DIYLC or something like that – trying to fit the designs onto smaller circuit boards. In the future I would probably just order a printed board that has the layout right on the board instead of doing everything from the ground up. For the graphics, my local library has a vinyl cutter, then I did a layer of epoxy on top. This is a bit of a finicky process. It would be nice to just have a kit where everything is straight forward. I think I would also prefer to do some sort of stencil etching into the metal enclosures, which would be more durable for kicking around.

There is a lot of talk in the Eurorack community about how kits are often more costly to the manufacturer because of all the labeling, instructions, packaging and support. I like the idea of building modular synthesizers, but in a way it would be smarter just to go to work for a couple of days and buy the modules, than spend months and months soldering, and troubleshooting with a multimeter and an oscilloscope. That being said, its still a good way to really understand how logic and electricity create sound structures.


Very cool! Graphics are awesome. I’m a big fan of bold lines and simplicity. Knobs look nice too.

Any chance of an Audulus emulation?? :wink: