Guide track

A guide track or ghost track is a recorded selection of music or song used as an aid in sound recording, filmmaking and performance. It is closely related to the click track, and the two are typically used in conjunction.

In sound recording, guide tracks are often used as a framework around which the additional tracks are built. Similar to demo recordings, they may contain simplified arrangements. Used primarily to aid musicians in synchronizing their performances—which may not be recorded at the same time—these tracks may or may not be included in the final mixed product.

In filmmaking, guide tracks are commonly used as an aid in lip synchronization, timing actions such as dance, and when musicians appear on camera. These tracks may be completed recordings, and are used to aid the actors in creating the illusion of live performance. See also dubbing (filmmaking).

Guide tracks are increasingly found in live music, which often relies on music sequencers to recreate recorded music on the stage. They may serve double duty as backup tracks, such as vocal harmonies created by singers who overlay multiple instances of their voices in the recording studio.

Singers may also use guide tracks to help them remain in tune with the musicians; these may not be audible to the audience. Inexperienced singers, or those with limited skills, may sing along with a foreground voice track. This last usage is essentially the same as lip synchronization, although the live singer's voice may in some cases be combined with the recorded vocals or the recorded track lowered in volume. Vocal guides are sometimes used both by professional entertainers and in amateur karaoke performances. This technique was used extensively by Milli Vanilli, and occasionally by Ashlee Simpson (especially in an infamous Saturday Night Live performance, before which she was having voice problems).