Fripp & Eno is a musical side-project composed of Brian Eno and Robert Fripp. The duo have released four studio albums, beginning with the 1973 album No Pussyfooting. The music created by this pair is entirely instrumental and has made extensive use of Frippertronics, a tape delay technique, combined with Fripp's guitar, the Fripp Pedalboard and Frizzbox (with subsequent sound treatments by Eno) along with Eno playing various keyboards, synthesizers and modified Revox A77 tape recorders. In 2015, Fripp & Eno were ranked No. 17 on Rolling Stone's list of the 20 Greatest Duos of All Time.