The heart of a TB303 synth recreated in modular format x0x xOx
https://www.crowdsupply.com/open-music-labs/x0x-heart-eurorackSelling a beautifully built and fully calibrated x0x‑Heart with the EI‑303 interface by
jean.pri, with few tweaks — a complete, performance‑ready TB‑303 voice in Eurorack format.
v.1.1
Implemented some tweaks kindly given by P4L modular.
Tuning control sensitivity decreased.
Max resonance increased.
Max decay increased.
Calibration stability improved: clean 4 octave doubling, ~ 2 cent deviation.
Added:
authentic tantalum capacitors,
precision 0.1% tolerance resistors,
high quality Alpha potentiometers.
EI‑303 adds:
- 303‑style control panel
- controls and CV for Saw/Square mix,
- Drive, Filter FM controls
- Invertible Accent/Slide knobs with led illumination,
and more intuitive, ergonomic layout for live tweaking.
- calibration controls - easily accessible.
Condition: fully working, clean build, accurately calibrated across 1–5 V, power cable + screws.
Shipping: France, Spain, Netherland, Portugal ~ 5 euro.
Germany - 12, US from 20 euro.
shipping within Belgium - 5€
Location:
* I am in Brussels (Woluwe, St. Lambert) - Belgium
* you can pick up the module here
Can send photo, video on request.
Feel free to contact

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