Open-source Eurorack

Open-source Eurorack modules — built in the open

Build logs that show every step, and plans you can build from: PCBs, firmware, panels — and the way there.

2: Modules in development
9: Series of build logs and articles
67: Chapters, written as the work happened

Fracanto - modular digital CAN-Bus Synthesizer

Featured: Pulser

a tight Eurorack clock on the RP2040

Pulser in development A clock module whose top priority is tightness: pulse generation runs in the RP2040's PIO hardware state machines, unaffected by the CPU. With demo video, build log and tempo control deep-dive.

Watasoge in development A digital wavetable sound generator on the STM32G431KB — the build log follows the journey from the first wavetable to firmware on the board.

All modules →

Why DIY Modular Synthesizers? — a personal note

I started experimenting with electronic music when I moved to Berlin in 1985 after finishing high school.

By attending Superbooth 2025, I found my way back into the world of electronic music after decades as a software developer, and discovered something new (to me): Eurorack modular synthesizers.

The fascination lies in the combination of electronics and software. You can generate sounds with analog components. You can develop firmware for microcontrollers, and you can combine both approaches.

Particularly interesting and useful is the modular design. You can create a small, dedicated module for each specific purpose and combine the modules into a — sometimes complex — larger whole. A principle that was fundamental and defining throughout my life as a software developer.

The emergence of artificial intelligence as a tool offers nearly unlimited possibilities and opens up an infinitely exciting field.