Theremins are made up of two antennas mounted on a box, and played by moving the hands around the antennas. They work using two oscillators, one with a fixed frequency and the other with a variable frequency. The combined frequencies of these oscillators results in a frequency within the audible range, with the pitch and volume determined by the movement of the user's hands. The right hand usually controls the pitch while the left controls the volume, although these may be interchanged.
Types of Theremins
Kinds of Theremins include the following:
Mic stand theremins
Mic stand theremins are mounted on microphone stands, allowing the sound to be amplified by microphones. The antennas are usually mounted six inches apart, providing a range of up to three feet. The stands are usually adjustable to accommodate users of different heights. Foot stand theremins
Foot stand theremins have large rubber boxes designed to rest on the floor. They may have one or two antennas that extend from the box up to the user's arm level. Lighter models often have adjustable antennas that allow them to be played on tabletops.
Choosing Theremins (Buying tips)
Pitch and playing range: Choose a theremin with a playing range of about three feet. This will allow better volume and pitch control, especially for beginners. For more versatility, look for a theremin with a pitch range covering five to seven octaves. Power: Choose a theremin that runs on 9-volt alkaline batteries or socket power. Make sure it consumes minimum power, ideally about three milliamps. A high-quality theremin should last 100 hours of play on a standard 9-volt battery.
Components: Choose a theremin with readily available components, so that you can easily find replacements for broken parts. If you are buying a secondhand theremin, make sure the part numbers and component values are still readable to make repairs easier.