Clean is overrated. If you’re ready for a little digital dirt in your synth life, powered by the open-source Arduino hardware, Marc Nostromo’s Squealer is for you. Built atop the wonderful, Arduino-based Pocket Piano kit by Critter and Guitari, it’s a full-blown, simple, digitally-gritty synthesis engine.

You get a monosynth, some fixed waveforms, a resonant filter, decay, and some aliasing tricks for extra grit. The big news: the Arduino Piano Squealer is now under a GPL license.

Official Arduino Piano Squealer Synth Page has everything you need
Announcement of GPL v3
All at

Here’s what it sounds like:

SAP+BOM+Dodgey Eighties Ringing Reverb:

Eery piano:

SAP+Flanging Mini KP: