The theremin, invented by Russian physicist Leon Theremin in 1920, is usually played without being touched by the performer. Two antennae, one for the theremin’s pitch and one for its volume, are used to control the instrument. As the performer moves their hands closer to or further from the antennae, the pitch and volume change. The theremin was patented in 1928 and licensed to RCA for manufacture, but the Wall Street Crash of 1929 hampered its commercial potential.
