Glitch Delay is a simple but fluid, musical effect for Eurorack modulars, with all the instructions free online. And it makes beautiful music, too.

Scott Pitkethly performs music as Cutlasses, and took on this project starting with the tiny, cheap, powerful Teensy USB prototyping platform. With that as the base, he created a Eurorack-compatible sound processor for modular systems. And, wow – sometimes simple, digital effects have their own special charm in music. Take a look – and love that lunchbox Euro case!

The firmware, schematics, and bill of materials and instructions are all online free, under an open license – so you can try creating one of these yourself, or even make and share your own modifications. The idea is to build some basic resources for people wanting to make their own audio processing modules.

You don’t have to restrict yourself to Eurorack hardware, though. Apart from potentially being of interest as desktop hardware or a guitar pedal, you can also run the same code as a plug-in your software host or on a mobile device, because it’s all built in JUCE. So, if you prefer a VST plug-in to a Eurorack module, you’ll want to check out the cross-platform plug-in:

Scott tells us a little bit about his inspiration:

To give you some background, I got into making my own hardware when I ended up building a MIDI pedal, so I could control Ableton whilst playing guitar. The ones on the market were either too big or too expensive. I’m a programmer by trade, so can handle coding, but still consider myself a bit of a novice when it comes to analogue electronics. That’s when I discovered Teensy, (similar to Arduino but smaller and faster). When I found out there was an audio library I started playing around with that. I made the AudioFreeze first:

I was inspired to make the Glitch Delay (probably needs a less generic name 🙂 ) after seeing some of the demos from the monome aleph [“audio computer”], and it coincided nicely with the release of the Teensy 3.6 which has 4x the memory, and a faster processor (than the 3.2). During development, I found debugging on the Teensy quite difficult (no debugger), so I wrote some code in JUCE to allow me to code on the Mac, keeping the interfaces the same, so I could find a lot of the bugs on the Mac, with a proper debugger!

All the source code for the Glitch Delay is shared on GitHub, along with the schematics, etc. I’ve learned from lots of schematics that other people have shared, so I like to share in return.

I used the Glitch Delay extensively on my album, and also made this video to demonstrate some of the effects I’ve made processing an old autoharp.

Scott has begun a series explaining how this all works; part 1 is already up with more on software coming soon:

What I love about the end of this story is, all the craft of working with the technology at this low level makes what is to me gorgeous, personal music with a raw aesthetic that seems interwoven with how it’s made. That is, the assembly of the code and hardware is tied up with the textures that result, in eerie, meditative digital sonic surfaces against organic acoustic rhythms. Have a listen:

Thanks, Scott! We’ll be watching – and trying this out!