Choosing a Theremin

by C. Chris Peters

The thing to watch for when choosing an instrument is its linear response. Check to see how evenly your hand movements are translated by the theremin. For example: as with string instruments like a guitar, you can see that the frets are spaced in shorter distances from one an other for producing higher notes, and further away from each other for the lower notes. If guitars where truly linear (which they will never be), all the distances between the frets would be the equal. Since theremins have no frets, the distance you move your hand from the pitch antenna to produce a scale should as consistent as possible. More expensive theremins generally have a more linear response to hand gestures than less expensive ones.

I have been using my Moog (then Big Briar) Etherwave theremin that I built from a kit in1996. It has never given me any problems.The Etherwave is considered by many thereminists to be a starter instrument because of its average linear response. I think the Etherwave is the best value for the money, sounds great, and as a performer, I have never been bothered by its particular linear response.

I recommend the building the Etherwave kit mainly because you get to know your instrument from the inside out and you save a few dollars besides. The circuit board comes pre-assembled and calibrated, so all you are really doing is putting it together. You will need to solder a few connections, so access to a soldering iron is a must. The biggest problem I had when assembling my instrument was finishing its wooden cabinet.

Recently Moog Music made a daughter board that allows the Etherwave to control other synthesizer instruments. This turns your stock Etherwave into an “Etherwave Plus”. This new board connects to synthesizers and effects devices that have voltage control inputs. It does not connect to MIDI or USB devices. Unless you have access to an analog synthesizer or signal processor with CV, Gate, and Trigger inputs, the new “plus” board is not useful.

There is another theremin kit from Paia that can be purchased via mail order. I have tried a few of these Paia’s and found them a lot fun to play but they not at all linear in their responses. Linear response is sort of a personal taste along with the kind of playing you are planning to do. I found the Paia "Theremax" model a little more difficult to play recognizable tunes than the Etherwave, but is great for all sorts of sci-fi woo woo effects. I have no experience with assembling the Paia kits so I cannot vouch for their level of difficulty, but I suspect you have to assemble and calibrate the circuit board yourself.

You can find lots of cheep theremin instruments advertised on the Internet. The ones I have seen are really half theremins in that they offer no way to control their volumes. They are just a pitch producing circuit. A complete theremin has ways to control both pitch and volume. I often use one of these half theremins with a guitar effects pedal called a Synth-Wah as an auxiliary special effect. I put my hand near it and it screams. The closer I get the louder and higher it wails!