Click track

A click track is a series of audio cues used to synchronize sound recordings, sometimes for synchronization to a moving image. The click track originated in early sound movies, where optical marks were made on the film to indicate precise timings for musical accompaniment. It can also serve a purpose similar to a metronome, as in the music industry, where it is often used during recording sessions and live performances.

The click track was sufficiently useful as a synchronization tool that it became part of standard recording technology, whether for films, radio or other sound recording and the click track was applied to one of the tracks on a multi-track tape recorder. By the late 20th century, particularly in the realm of sound synthesizers and digital recording, the click track became computerized and synchronizing different instruments became more complex, whereupon the click track was largely supplanted by SMPTE timecode.

Click tracks were also once very important in the creation of accurately timed music such as radio/TV spots (commercials) and other timed production music. In this type of use a rhythm section or ensemble would play all instruments to a click track. With the use of MIDI sequencing in the '80s and '90s it became possible to build an entire music track that was accurately timed without depending solely on only a click track. Computer based MIDI sequencing programs are still used in the creation of music. The MIDI sequencer generated track can be used with only MIDI controlled instruments or embellished with real instruments played by musicians. The musicians who embellish the tracks created with MIDI sequencer essentially play along with the already timed piece of music. In many cases all of the MIDI instrumentation is replaced by actual musicians.

The click track may be used as a form of metronome directly by musicians in the studio or on stage, particularly by drummers, who listen via headphones to maintain a consistent beat. One can think of a click track as essentially being a kind of metronome except that it is fed through headphones to one or more of the musicians during a recording or performance. It is also not uncommon for musicians or engineers to subdivide click tracks at slow tempos (for instance, below 70 BPM) into smaller parts, with, e.g., a click on the start of a bar and a beep on every individual 1/4 (or 1/8, or 1/16, etc.) note.

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