Russian electrical engineer Leon Theremin demonstrates his new invention the aetherphone, or " Theremin," on August 5th of 1920. With the invention, musical tones are produced by electronic impulses interacting with ultrasonic circuits, oscillating radio tubes and hand movements of a player. The eerie, other-worldly sounds produced by the instrument became the trademark sound effect used in early Hollywood Sci-Fi movies and enjoyed a revival in the last decade of the 20th century.

On August 12, 1920, jazz saxophonist Charlie "Bird" Parker is born. A co-founder of "bebop," Parker was not only a technical wizard on the sax but a genius improviser who revolutionized jazz. As with all great innovators, after 1950, it would be nearly impossible to be a jazz musician without seriously devoting attention to the recordings and stylings that Parker ushered into the idiom.

Alban Berg completes his famous opera, Wozzeck, arguably the most popular and well-received piece of all of the twelve tone repertoire. The opera would not receive its premiere until 1925.

Mamie Smith notched her place in American music as the first black female singer to record a vocal blues. That record was "Crazy Blues" (rec. Aug. 10, 1920), which sold a million copies in its first six months.