The Theremin named after the Russian physicist Leon Theremin ( Lev Termin in Russian) is an early electronic musical instrument somewhat unique in that it is played without physical contact.
|As Wikipedia describes the theremin's control:|
The instrument's controlling section usually consists of two metal antennas that sense the relative position of the thereminist's hands and control oscillators for frequency with one hand, and amplitude (volume) with the other. The electric signals from the theremin are amplified and sent to a loudspeaker.Here is an early clip of Theremin demonstrating the instrument:
Theremin invented another listening device called The Thing. Disguised in a replica of the Great Seal of the United States carved in wood, in 1945 Soviet school children presented the concealed bug to U.S. Ambassador as a "gesture of friendship" to the USSR's World War II ally. It hung in the ambassador’s residential office in Moscow and intercepted confidential conversations there during the first seven years of the Cold War, until it was accidentally discovered in 1952.