Strange Musical Instrument: Theremin

@ wiki
The theremin, theramin, or thereminvox, also known as an aetherphone is one of the earliest fully electronic musical instruments. It was invented by Russian inventor Léon Theremin in 1919, and it is unique in that it was the first musical zinstrument designed to be played without being touched. The controlling section generally consists of two metal antennas to sense the relative position of the player's hands. These sensors control audio oscillator(s) for frequency from one hand, and volume from the other. The electric signals from the theremin are amplified and sent to a loudspeaker.

To play the theremin, the player moves his hands around the two metal antennas, which control the instrument's frequency (pitch) and amplitude (volume). The theremin is widely associated with "alien", surreal, and eerie-sounding portamento, glissando, tremolo, and vibrato sounds, due to its use in film soundtracks such as Spellbound, The Lost Weekend, Ed Wood, Mars Attacks! and The Day the Earth Stood Still. Theremins are also used in art music (especially avant-garde and 20th century "new music") and in popular music genres such as rock and pop.

More info (including technical details)

Most people have probably heard the theremin through old sci-fi movies in which is was very popular. In this clip, from The Day the Earth Stood Still, you first hear the theremin as the almost female sounding high voice.

In this next clip the theremin is played in a more harmonious way featuring the classical piece "Clair de lune".