Open.Theremin is an open source hardware and software project by Urs Gaudenz of Gaudi Lab with the aim of building the next digital generation of the legendary music instrument developed in the ’20s by the Russian inventor professor Leon Theremin. The project is documented under a open license and uses Open.Theremin.UNO, an Arduino or Genuino Uno shield featuring a digital mixer, combined 12 bit audio and CV out, audio jack on the bottom for more compact design, two completely separate antenna circuits:
The theremin is played with two antennas, one to control the pitch and one for volume. The electronic shield with two ports to connect those antennas comprises two heterodyne oscillators to measure the distance of the hand to the antenna when playing the instrument. The resulting signal is fed into the arduino. After linearization and filtering the arduino generates the instruments sound that is then played through a high quality digital analog audio converter on the board. The characteristics of the sound can be determined by a wave table on the arduino.
Most theremins on the market are either expensive or then not really playable. That’s how I decided to design a playable, open and affordable theremin. The first version was modular and difficult to program. Then I decided to redesign it as a shield to fit on the Arduino.UNO. This was a big success and many people could start using it, change the sounds and adapt it to their own application. The whole design is open source and documented on the website. I produced a small batch of the shield that can be bought through the small batch store on the website.
Watch the video below with Coralie Ehinger, a Swiss theremin player and organizer of the first Swiss theremin festival N / O / D / E, playing the instrument: