Derek Showard,[1] better known by the stage name GrandMixer DXT, is an American musician, and the first DJ to use the turntable as a musical instrument.

Early in his career, he was known as Grand Mixer D.ST, a reference to Delancey Street on the Lower East Side of Manhattan, New York City.

[citation needed] He was the first person to establish the turntable as a fully performable and improvisational musical instrument (Alberts 2002).

He is also credited with helping to popularize DJing through his scratching on Herbie Hancock's single "Rockit", from the Bill Laswell and Material produced album Future Shock.

[4] With Ginger Baker With Herbie Hancock With Jah Wobble With King T With Bill Laswell With Praxis With Sly and Robbie D.ST: The Home Of Hip Hop (Celluloid, 1985)