Backing track

A backing track is an audio recording on audiotape, CD or a digital recording medium or a MIDI recording of synthesized instruments, often of rhythm section or other accompaniment parts that live musicians play or sing along to. Backing tracks enable singers and bands to add parts to their music which would be impractical to perform live, such as string section or choir parts which were recorded in the studio.

Bands or solo musicians may use backing tracks to add extra instrumental or vocal tracks to a live performance, to enhance the sound (as in the employment of doubled backing vocals) or to replicate more closely the instrumentation heard on a recording (as in the use of additional recorded parts such as string sections which would be costly to reproduce live.) A singer or vocal group performing without a backup band may sing along to pre-recorded music. A music track without lead vocals may also be called a karaoke, minus-one track or playback. Music backing tracks are also available for instrumental practice and jamming by jazz musicians, to help beginning to intermediate performers learn to improvise over chord progressions. Backing tracks are also known as jam tracks. If bought commercially, backing tracks often use session musicians to play the instruments and backing vocals, rather than using the original recording of a song, because the rights to use the original performance of the backing parts of a song by a well-known band would be very costly to purchase.

In electronic music, some parts which have been programmed are too fast or complex to be played by a live musician. Backing tracks are also used when some or all members of a group are miming the playing of their instruments, lip-synching or using guide tracks.

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Wikipedia