The theremin is an electronic musical instrument named after its inventor, Léon Theremin, who patented the device in 1928. The theremin is controlled without physical contact by the thereminist (performer). 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.