Scratching

Scratching, sometimes referred to as scrubbing, is a DJ and turntablist technique used to produce distinctive percussive or rhythmic sounds and sound effects by moving a vinyl record back and forth on a turntable while optionally manipulating the crossfader on a DJ mixer. While scratching is most commonly associated with African-American hip hop music, where it emerged in the mid-1970s, it has been used in the 1990s and 2000s in some styles of pop and in nu metal. Within hip hop culture, scratching is one of the measures of a DJ's skills. DJs compete in scratching competitions at the DMC World DJ Championship and IDA (International DJ Association, formerly known as ITF (International turntablist Federation). At scratching competitions, DJs can use only scratch-oriented gear (turntables, DJ mixer, digital vinyl systems or vinyl records only). In recorded hip hop songs, scratched hooks often use portions of other songs.

A rudimentary form of turntable manipulation which is related to scratching was developed in the late 1940s radio DJs (music program hosts) or the radio program producers who did their own technical operation as audio console operators. It was known as back-cueing, and was used to find the very beginning of the start of a song on a vinyl record groove. This was done to permit the operator to back the disc up (rotate the record or the turntable platter itself counter-clockwise) in order to permit the turntable to be switched on, and come up to full speed without ruining the first few bars of music with the "wow" of incorrect, unnaturally slow-speed playing. This permitted the announcer to time her or his remarks and start the turntable a scant moment before she or he actually wanted the music on the record to begin.

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