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The newest Open.Theremin boards are produced in small batches and sold here. The series are produced in high quality desktop manufacturing and all boards are 100% tested.


Open.Theremin.UNO Bare Shield Kit

Open.Theremin.UNO shield. Add an Arduino.UNO and two antennas to it and you get a fully playable theremin.
The pins need to be soldered on the board using a conventional soldering iron.


Get your fully assembled and tested Open.Theremin.UNO shield for 48 euro including shipping worldwide.
Payment by PayPal. Be sure to set your correct shipping address.


CURRENTLY SOLD OUT. Please see the news blog for updates.
If you want to be informed when the first batch of the new theremins are ready, please use this form.


Open.Theremin.UNO V2 Bare Shield Kit


Open.Theremin.UNO Shield plus Extension Kit

The extension kit provides you with mechanical parts to set up the open.theremin as well as electronic components to expand its functionality.
With the current expanded software you can choose different sounds and adjust the volume with the two knobs.


  • 2x Antenna plugs for board mounting
  • 2 x potentiometers and knobs
  • Front panel
  • Spacers and screws and washers for mounting antennas and front panel
  • 5 mm LED blue
  • Acrylic pad to attach camera stand (1/8" UNC)
  • Jumper for CV setting

Antennas are NOT included in the kit as they are to bulky to ship.
You can easily make them your self from any conductive tubing. For the kit best use tubing with 4 mm inner diameter.
The open.theremin can be adjusted to different types of antennas.

Get your fully assembled and tested Open.Theremin.UNO plus the extension kit for 69 euro including shipping.
Payment by PayPal. Be sure to set your correct shipping address.


CURRENTLY SOLD OUT. Please see the news blog for updates.
If you want to be informed when the first batch of the new theremins are ready, please use this form.


Open.Theremin.UNO V2 Shield plus Extension Kit


For questions please see the instruction below, read the frequently asked questions (FAQ) or contact me.



In English:



Auf Deutsch:


In Italiano:



Italian translation kindly provided by Massimiliano Lucchina.

CV and MIDI Instructions


You can use usb for midi by Hairless-Midi (http://projectgus.github.io/hairless-midiserial/)

You find all MIDI-neccessary code by searching _MIDI in the sketch
1. Move or copy directory MIDI to sketchbook/libraries (http://playground.arduino.cc/Main/MIDILibrary)
2. Set Variable _MIDI = 1
3. Start Hairless-Midi (Now a Midi-Port is available in your DAW)
4. Enjoy

Note: Set Portamento on your Midi-Synthesizer or DAW-Plugin to get a Glide
Volume-Antenna is setting Velocity and Pitch Antenna is setting Tone



You find all CV-neccessary code by searching _CV in the sketch

1. Place the Jumper on the Shield
2. Set Variable _CV = 1
3. Enjoy

NOTE: CV is VOLT/OCTAVE (synthesizers like moog, korg, etc) with a range from 0 to +5V and it runs perfect with my minimoog.
if your synthesizer need HERTZ/VOLT (many synthesizers like yamaha, etc) you have to add or substract some value to the volt result to get the hertz-value you need.
you can find a hertz/volt table under (https://en.wikipedia.org/wiki/CV/Gate)
i dont have gear that needs HERTZ/VOLT, so i cant test...
the theremin will not send a gate signal, so you have to press or tape a key on your synthesizer.


Instructions and Implementation by Daniel Selbersuess, 2015-08-27

Open.Theremin.UNO – Il vero Theremin con Arduino

Open Theremin è un progetto hardware e software open source. L'obiettivo è di costruire una nuova generazione, una versione digitale del leggendario strumento musicale. La nuova versione di Open.Theremin.UNO si basa sulla popolare scheda di sviluppo Arduino, la quale può essere riprogrammata facilmente. Costruisci il tuo theremin completo dei controlli di velocità e volume. Suonare semplicemente muovendo le mani in prossimità delle antenne.

Abbiamo oltre due anni di esperienza nella costruzione di theremin digitali di buona qualità e dal prezzo accessibile, questo ci ha portato a questo nuovo progetto, migliorato e semplificato, dotato di un nuovo mixer digitale combinato a 12 bit e uscita CV, un jack audio sulla parte inferiore ed design più compatto. Due circuiti di controllo per le antenne completamente separati e due nuove manopole (opzionale). Molte idee e preziosi consigli sono stati integrati nella nuova versione grazie ai collaboratori, in open.theremin.UNO.

Open.Theremin.UNO la scheda con le antenne connesse.



• Controlli della velocità e del volume con eccellente linearità e sintonizzazione digitale
• Scheda compatibile con Arduino per una facile programmazione
• Convertitore digitale-analogico a 12 Bit per generare l’uscita audio
• Le forme d’onda generate possono essere riprogrammate liberamente (memorizzate in una tabella)
• Il connettore audio può essere riprogrammato per fornire la tensione di controllo (CV)
• Connettore audio o di tensione di controllo a bordo
• Alimentazione tramite porta USB, non necessita di un alimentatore aggiuntivo
• Possibilità di alimentazione a batteria
• Design a basso profilo con component in SMD per una semplice spedizione
• Contatti a vite o a saldare per collegare le antenne
• Interfaccia ad un pulsante
• La distanza delle mani dalle antenne vengono convertite in un valore digitale che può essere utilizzato per applicazioni diverse dall’ uso come theremin
• Predisposizione per saldare un potenziometro analogico (o encoder digitale)
• Piazzola per saldare un eventuale filo di messa a terra direttamente sulla scheda


Puoi acquistare il tuo Open.Theremin.UNO anche con kit di estensione opzionale nel nostro Piccolo negozio on line.


Tradotto dall'inglese da Massimo Lucchina

Thérémine PC Software

While the Open.Theremin.UNO has it's own sound generator and can be played as stand alone instrument the Thérémine software allows you to connect your theremin to a computer via USB and largely extend the functionality.


The Thérémine software was developed by Vincent Feuvrier and all credits go to him.

The software is open source and licensed under a GNU General Public License. See here.



The Thérémine audio program reads realtime pitch and volume data from the Open.Theremin.UNO (or any other USB Arduino Theremin), and generates high quality audio signal emulating a realistic instrument.
To use the software with the Open.Theremin.UNO you need to install new code to the arduino that comes with the software.



The software adds the following options to the Open.Theremin.UNO:

  • Computer generated high quality audio with different sound engine
  • Normal and inverse pitch and volume characteristics
  • Linearity correction
  • Half-tone scale
  • Selectable range
  • Visual feedback
  • Software and hardware calibration
  • Microsoft wave audio output support (Windows only);
  • OpenAL support;
  • ASIO audio output support;
  • custom file format (loop bank .lbk) to manage audio sample banks for internal synthesizer;
  • advanced wave file analyzer to import and simulate other instruments using a recorded wave file.

The software package comes with a "Loop bank manager", whose purpose is to extract stationary, looping samples from recorded wave files. It allows importing new instrumental tones into Thérémine.

Thérémine is written using Lazarus. Linux and Mac support is planned but not yet implemented (and help is welcome for Mac compatibility).


Download the Théremine Software here.

There is a Windows installer and a Portable Windows version.