What on earth is a Theremin?

The theremin, also know as aetherphone / etherophone or termenvox / thereminvox is an early electronic musical instrument controlled without contact from the player. It was invented by Russian scientist Leon Theremin and was first demonstrated in 1920. It predates the modern synthesizer by about 40 years, but its uniqueness stems from the fact that it is the only instrument that is played without actually being touched. Its electronic circuits are controlled by two antennas, left and right of the instrument, toward which the player moves his or her hands. The closer the right hand to one antenna, the higher the pitch. Similarly the proximity of the left hand to the other antenna controls the volume. The theremin has a range well in excess of eight octaves, and is capable of all kinds of strange effects. These sounds have been put to use in science fiction and other films including Alfred Hitchcock's Spellbound (1945) and Robert Wise's The Day the Earth Stood Still (1951). This unique instrument has also been used on The Beach Boys' song "Good Vibrations." The late Clara Rockmore was the theremin's greatest virtuoso, and the instrument and its inventor were profiled in the documentary Theremin: An Electronic Odyssey (1994).