====== Theremin ======

The **theremin** or **thereminvox** is one of the earliest fully electronic musical instruments.  Invented in 1919 by Russian Léon Theremin, the theremin is unique in that it requires no physical contact in order to produce music and was, in fact, the first musical instrument designed to be played without being touched.  The instrument consists of a box with two projecting radio antennae around which the user moves his or her hands to play.  

[[http://www.theremin.info|{{Image:Animatedleon.gif|Léon Theremin plays his invention.}}]]

=====  Overview  =====

To control the theremin, the musician stands in front of the instrument and moves his or her hands in the proximity of two metal antennae, the distance from the antennae determining frequency (pitch) and amplitude (volume) of the resulting sound.  Small movements of the hands can create a tremolo or vibrato.  Typically the right-hand controls the pitch and the left hand is used for the volume although some left-handed thereminists exist.

Based on the principle of heterodyning oscillators, the theremin generates an audio signal by combining two different but very high frequency radio signals.  The capacitance of the human body close to the antennas causes pitch changes in the audio signal, in much the same way that a person moving about a room can affect television or radio reception.  By changing the position of the hands relative to the vertical antenna, a performer can control the frequency of the output signal.  Similarly, the amplitude of the signal can be affected by altering the hand's proximity to the looped antenna.

A careful combination of movements can lead to surprisingly complex and expressive performances.  Typically, theremin sounds mostly consist of glissandi, however it is possible for a skilled performer to produce staccato notes.  Although theremin players do not need to have perfect pitch, the thereminist must rely on memory and careful listening to play the instrument accurately, which is considered difficult to master.

=====  History  =====

The theremin was originally the product of Russian government-sponsored research into proximity sensors.  The instrument was invented by a young Russian physicist named Lev Sergeivich Termen (most commonly known in the West as Léon Theremin) in 1919, followed closely by the outbreak of the Russian civil war. After rave reviews at Moscow electronics conferences, Theremin demonstrated the device to Bolshevik leader Vladimir Lenin personally. Lenin was so impressed with the device that he began taking lessons in playing it, commissioned 600 of the instruments for distribution throughout the Soviet Union, and sent Theremin on a trip around the world to demonstrate the latest Soviet technology and the invention of electronic music.  After a lengthy tour of Europe, during which time he demonstrated his invention to packed houses, Theremin found his way to America, where he patented his invention in 1928 ([[http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO1&Sect2=HITOFF&d=PALL&p=1&u=/netahtml/srchnum.htm&r=1&f=G&l=50&s1=1661058.WKU.&OS=PN/1661058&RS=PN/1661058|US1661058]]).  Subsequently, Theremin granted commercial production rights to RCA.

Although the RCA Thereminvox, released immediately following the stock market crash of 1929, was not a commercial success, it fascinated audiences in America and abroad.  Clara Rockmore, widely considered the greatest thereminist ever, toured to wide acclaim, performing a classical repertoire in concert halls around the United States, often sharing the bill with Paul Robeson.  In 1938, Theremin was kidnapped from his New York apartment by Soviet agents, and forced to return to the Soviet Union and made to work in a //sharashka//, or a .  Theremin would not return to the United States until 1991

After a flurry of interest in America following the end of the Second World War, the theremin soon fell into disuse with serious musicians mainly because newer electronic instruments that were easier to play became available.  Still, among a small group of enthusiasts, interest in the theremin remained high.

As a high-school student, future synthesizer guru Robert Moog began his career building theremins in the 1950s.  Moog published a number of articles about building theremins and also sold theremin kits that were intended to be assembled by the customer.  Moog credits what he learned from the experience as leading directly to his groundbreaking synthesizer, the Minimoog.  Today Moog Music is the leading manufacturer of performance-quality theremins.

=====  Similar Instruments  =====

The '"Ondes-Martenot"' uses also the principle of [[heterodyne | heterodyning]] [[oscillator|oscillators]], but it is touched while playing.

The '"Tannerin"' does not use heterodyning oscillators and is touched while playing, but also allows somewhat-discrete control of the frequency range.

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