Leon Theremin was born on August 15, 1896 in St. Petersburg, Russia. In 1919, he invented an electronic device known as the theremin, which was a unique musical instrument that could be played without physical contact. Rather than plucking strings or pressing keys, the musician need only move their hands around antennas located on the device.
The device became a popular curiosity and he proceeded to tour Europe in order to demonstrate it. In 1928, he moved to New York City in the United States, where he played a theremin in the New York Philharmonic Orchestra in 1928. In 1929, he was granted a patent for the device by the United States. He decided to give RCA the rights to manufacture and sell the theremin for a lump sum payment and a percentage of the sales.
In the early 1930s, Theremin purchased a laboratory in New York that he used for experimenting with electronic musical instruments. One of the products of his lab was the Rhythmicon, which was purchased by Henry Cowell, a composer. In 1930, a group of ten "thereminists" performed at Carnegie Hall.
Theremin also began researching a method to cause lights and sound to respond to the movement of dancers. His system became popular with ballet and dance clubs throughout the country. While working with the American Negro Ballet, he fell in love with a ballerina named Lavinia Williams and married her, despite the scandal regarding her race.
In 1938, he moved back to the Soviet Union for an unknown reason. His wife, Lavinia, was left behind and claimed that he had been seized by Soviet officials. Later, it was revealed that KGB agents had forced him to return and that he had been sent to Butyrka Prison. A short time later, he was forced to labor in the gold mines of Kolyma. Eventually, he was allowed to work in a laboratory with some other scientists, including Andrei Tupolev and Sergey Korolyov.
While working for the Soviet Union, Theremin was forced to develop a covert listening device that used radio transmission to transmit sound to a receiver. The device became known as the passive cavity resonator and was difficult to detect since it only operated while it was being listened to. The KGB used the device to bug the office of the American ambassador to the Soviet Union.
Theremin also invented an motion detector to allow for the automatic opening of doors as well as a burglar alarm. In the 1970s, he also began tutoring his niece, Lydia Kavina, on the playing of the theremin. She remains one of the most skilled theremin players in the world.
In 1991, Theremin was finally allowed to return to the United States, following the collapse of the Soviet Union. He decided to return to Russia after visiting the United States and died on November 3, 1993.