“Revolution 9” is a recorded composition that appeared on the Beatles’ 1968 eponymous LP release (popularly known as The White Album). The sound collage, credited to Lennon–McCartney, was created primarily by John Lennon with assistance from George Harrison and Yoko Ono. Lennon said he was trying to paint a picture of a revolution using sound. The composition was influenced by the avant-garde style of Ono as well as the musique concrète works of composers such as Edgard Varèse and Karlheinz Stockhausen (whom Paul McCartney had been listening to in 1966, inspiring his ideas for “Tomorrow Never Knows” on the Beatles’ album Revolver).
The recording began as an extended ending to the album version of “Revolution.” Lennon then combined the unused coda with numerous overdubbed vocals, speech, sound effects, and short tape loops of speech and musical performances, some of which were reversed. These were further manipulated with echo, distortion, stereo panning, and fading. At over eight minutes, it is the longest track that the Beatles officially released (see Carnival of Light).