What’s a theremin? You wave your hand through the science flying around in the air and sound comes out. No, seriously. It’s an early electronic musical instrument, first patented by Léon Theremin in 1928. The “thereminist” creates the sound by waving their hand in the air near the device’s antenna. In doing so, the musician becomes part of the electrical circuit between the device, the amplifier/speaker, and the ground. The circuitry inside compares a base signal with the human-affected signal, and the difference comes through the output to be amplified and heard.
Although pre-assembled theremins are available, it is much more fun and interesting to get the parts and build your own. There are also many different designs to choose from. Some have two antennae, one for pitch, one for volume, but those are much more complicated and work on a slightly different electrical principle. We chose a simple design that makes use of a component known as a digital logic inverter (black rectangular things). It’s exactly what it sounds in. Zero goes in, one comes out,
and vice versa. In an analog application such as this, we can use them to make oscillators.
We built three altogether. I joined Artvoice Webmaster Anthony DiPasquale (who masterminded this project) and Pine Fever trumpet player, Alex Cline. A couple hours later, we had them working, all on the first try.
You can build your own based on this kit from harrisoninstruments.com. You can also do as we did, and buy the circuit board from them, and purchase the parts separately from a vendor such as mouser.com, and save yourself some money.
After firing them up, we put them in their own cases. Any box will do, as you can see. I chose a plastic container from the dollar store. Anthony used a cardboard box.
I later discovered that placing it on a music stand increased it’s pitch range dramatically. The music stand becomes part of the circuit and acts like an antenna. There is a tiny calibration screw on the trim pot (blue thing), and a knob on the outside to dial in the sound for each use.
The theremin has been in music for movies and television for decades, as well as some more serious musical compositions. Chances are, you have heard it somewhere, but just didn’t know it. Check out the video below of thereminist Peter Pringle performing “Over the Rainbow” on a 1929 RCA theremin that once belonged to the late Hollywood musician Dr. Samuel Hoffman.
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