Beinhorn started his professional career as a musician, playing keyboards in Bill Laswell's band, Material (originally the backing band for Daevid Allen's New York Gong LP, 1979) during the early 1980s. He worked with the jazz musician Herbie Hancock, performing on Hancock's Future Shock album, which contained the hit single "Rockit". Like most tracks on the album, except for the title track, "Rock It" was co-written by Beinhorn and Laswell, originally for the follow-up album to Material's One Down before Hancock became involved. "Rockit" quickly became a Billboard #1, and is regarded[by whom?] as one of hip hop's seminal hits; it was the first release to contain recorded DJ scratching.
Looking for the best way to capture a broad frequency range during the recording process, Beinhorn devised the Ultra Analog Recording format. This process utilizes two inch magnetic tape, running on a custom built 8 track head stack.