The Moog Etherwave Standard Theremin is one of the oldest electronic instruments, and is the only known synthesizer that you play without touching! Think Beach Boys Good Vibrations! What is a Theremin? The theremin is one of the oldest electronic instruments, and the only one known that you play without touching. Moving your hands in the space around its antennas controls pitch and volume. Like the Ethervox, the Etherwave is an authentic adaptation of inventor Leon Theremin's original design.