The emergence of multitrack recording

Photograph of a reel to reel tape recorder

© istockphoto.com / Janis Dreosti

Multitrack recording (or 'multitracking'), is a way of recording music in which separate recordings of multiple sound sources are made which are then used to create a single recording. Within this process each instrument or voice is recorded on to an individual 'track' (often at different times) and can then be played back simultaneously. Each track can also be mixed to the correct volume through a mixing desk and a variety of audio effects (such as reverb, delay, compression etc) can be added. This is the most common method of recording popular music and virtually all popular music is now made in this way.

Multitrack technology was first developed in the late 1940s after the introduction of magnetic tape as a means of recording. This new medium allowed for separate recordings to be made on different parts of the tape's surface, which in turn could be played back at the same time. Multitracking was developed by the US company Ampex and through the experiments of the guitarist Les Paul. By 1954 Ampex had produced the first eight-track tape machine at Paul's request, but eight-track machines remained rare within the industry until the late 1960s. Nevertheless, the techniques that Paul pioneered would become central to the way in which music is recorded, and have remained so to this day.

Multitracking involved several leaps forward, the results of which were that music could be recorded in new ways. Overdubs (the layering or replacement of differing tracks) allowed musicians to re-record particular parts or bolster the overall sound by layering instruments (often through 'double tracking', the practice of recording the same musical material twice to give the impression of multiple parts). Musicians could now play to a 'cue mix' (the name for what happens when performers hear the backing track isolated in headphones as they overdub). Multitracking also allowed for the 'bouncing' of tracks, in which two or more tracks are mixed at appropriate levels and then recorded on an unused track. The original tracks can then be erased, thus freeing them up for the recording of more instruments.

An early innovator in multitrack recording was Atlantic Records' chief engineer Tom Dowd. Dowd acquired an eight-track prototype in the late 1950s and used the new technology to split the rhythm section into separate tracks. Through the process of equalisation, this allowed him to emphasise the bass and high frequencies of particular parts (see Théberge 2003a, 642).

Not only did these innovations help change the recording process, they also went on to alter the sound of recordings themselves and to become a central creative tool for musicians in a number of genres. As the number of tracks at the disposal of musicians grew, many acts in the rock era used multitrack recordings to create ever more elaborate arrangements with layers and layers of differing sounds. This new use of technology was in keeping with the way in which many musicians saw rock music as a progressive form with endless possibilities. Late 1960s acts such as the Beach Boys, the Moody Blues and the Beatles used the sounds, layers and effects of multitrack recording to push at the boundaries of recorded popular music. During the 1970s the recording industry took these technologies to their logical conclusion and began using 16-, 24-, 32- and 48-track studios.