Overdubs

Overdubbing (the process of making an overdub, or overdubs) is a technique used in audio recording, whereby a performer listens to an existing recorded performance (usually through headphones in a recording studio) and simultaneously plays a new performance along with it, which is also recorded. The intention is that the final mix will contain a combination of these "dubs".

Tracking (or "laying the basic tracks") of the rhythm section (usually including drums) to a song, then following with overdubs (solo instruments, such as keyboards or guitar, then finally vocals), has been the standard technique for recording popular music since the early 1960s. Today, overdubbing can be accomplished even on basic recording equipment, or a typical PC equipped with a sound card, using digital audio workstation software.

Perhaps the earliest commercial issue of recordings with overdubs was by RCA Victor in the late 1920s, not long after the introduction of electric microphones into the recording studio. Recordings by the late Enrico Caruso still sold well, so RCA took some of his early records made with only piano accompaniment, added a studio orchestra, and reissued the recordings.

A foreshadow of overdubbing can be seen with Sidney Bechet, an American jazz musician who made a pair of famous overdubbed sides in 1941 entitled "The Sheik of Araby" and "Blues of Bechet". The multi-instrumentalist recorded the clarinet, soprano, tenor saxophone, piano and the bass and drum parts for both songs, and then he recorded each track separately on top of one another to create two single tracks . The recordings were then issued as "Sidney Bechet's One Man Band"

In 1948 experiments mixing sound effects and musical instruments made by Pierre Schaeffer at the Radio Télédiffusion Française experimental studio in Paris led to Étude aux Tourniquets, the first avant garde composition using recording as a composition technique, recorded and mixed directly on acetate records as tape recorders were not yet available. Similar sound collage experiments had been made by Edgard Varèse in the 1920s but Varèse, also a French composer, wrote scores later played live by musicians. As from 1949, Schaeffer composed and recorded on acetates with Pierre Henry (Symphonie pour un homme seul, 1950), who also recorded with Varèse in 1954. Together they used some of the earliest tape recorders available in the early 1950s.

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