Posts with «theremin» label

The Infrared Theremin

The traditional theremin is more or less an audio oscillator with two metal rods. Using proximity sensing, one rod controls the pitch of the oscillator and the other controls the volume. [Teodor Costachiou] apparently asked himself the excellent question: Why does the proximity sensor have to use capacitance? The result is an Arduino-based theremin that uses IR sensors to determine hand position.

[Teodor] used a particular type of Arduino–the Flip and Click–because he wanted to use Click boards for the IR sensors and also to generate sound via an MP3 board based around a VS1053. The trick is that the VS1053 has a realtime MIDI mode, and that’s how this Theremin makes it tones.

Of course, a real theremin is distinctly analog. A tiny change in hand position creates a small change in the output. With digital sensors and sound generation, the output is more in discrete steps, but according to [Teodor], the effect isn’t bad. We were hoping for a video (or, at least, an audio clip) but [Teodor] pleaded that he’s not a musician. He did include a video of a real theremin performance with his post, and you can see it below. But that’s a real analog theremin.

If you want to build something more traditional, have a look at Open Theremin. Or, if you want to get your exercise, how about trying a terpsitone. If you do, and can play the theme to The Day the Earth Stood Still, we’d love to see the video. Meanwhile, if you didn’t know the theremin had an espionage connection, you haven’t been staying current on Hackaday posts.

Filed under: Arduino Hacks, musical hacks

The real open source Theremin on Arduino

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:

Arduino Blog 11 Jan 18:43

Arduino-based theremin

Theremin is one of the most exiting musical instruments ever made, mainly because of its “quite odd” playing method. Infact, its working principle is based on near-filed coupling between the hands of the theremin player and two metal antennas, used to determine the pitch of a variable-frequency oscillator and to adjust the volume of the output signal, respectively.
Several theremin implementation are possible, such as the “original” analog one (based on the mixing of two sine waves originated by a fixed-frequency oscillator and a variable-frequency one) and those based on digital techniques.
LabIII guys implemented a nice and simple Arduino theremin module, based on a TTL LC-type oscillator, usable not only to play electronic music, but also as a generic sensing-device, for example to control motors and/or to work with Processing, Max etc.
The detailed description of the project, together with schematics and source code, can be found here.



Arduino Blog 21 May 19:29