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Design, creation and inspiration for
electronic musical instruments

Recent Products

New year, new modules!

Posted on Dec 27, 2017 by rutgervlek

Dear synth lovers,

I’m happy to announce two new fruits of this year’s creativity:

Marble – Dual spectral tilt tone control

Dendrites – A multicharacter multimode VCF / phaser

Both modules can now be ordered, and first units will be shipping on February 1st, 2018.

I wish you a very happy and musical 2018!


TLC for the JX-3p

Posted on Sep 15, 2017 by rutgervlek

I’m happy to announce the result of a fruitful collaboration. This time it’s not a Eurorack module, but a MIDI expansion kit for the Roland JX-3P synthesizer. With some tender loving care, it brings the JX-3P’s MIDI capabilities up to modern standards.


  • real-time control over all JX-3P parameters with standard MIDI CC messages (from a sequencer or MIDI controller)
  • velocity sensitivity (via MIDI)
  • selectable MIDI receive channel (1-3)
  • loading new patches into the JX-3P via MIDI

And for PG-200 owners:

  • simultaneous control via MIDI input and PG-200
  • transmission of MIDI CC messages from PG-200, for recording in sequencer, or controlling other MIDI devices
The expansion kit can now be pre-ordered here, and first units will be shipped in october.

Listen to the interview and win a Crux!

Posted on Mar 17, 2017 by rutgervlek

In the fall of 2016 I was approached by Markus Völter to do an interview on synthesizers for his Omega Tau PodCast station. The PodCast shows normally contain in-depth interviews on science and technology, but for this interview we stretched it all the way from science to art. We took an entire morning and part of the afternoon in my studio to talk and play examples on different instruments. Markus even turned our vocoding efforts into an Omega Tau jingle!

You can listen to the complete interview here: http://omegataupodcast.net/237-synthesizers/

But there’s more! As a former scientist I really admire how Omega Tau makes these long in-depth topics accessible in a pleasant way to a wide audience. It is driven by sheer enthusiasm for the topics on show, and many unpaid hours are put into it. I’d like to support that, so I decided to give away one free Eurorack module: one River Crux dual VCA + free shipping to anywhere in the world. A winner will be randomly drawn from those of you who listen to the interview and answer the following question:

“What type of MiniMoog does Rutger have in his studio?”

Send your answer to me before june 1st

(close friends and relatives excluded from participation 🙂 ).