The Roland G-707 is an electric guitar used by Prince and Wendy Melvoin. It can be used as an electric guitar or, with the Roland GR-700 floor unit, it can form part of a guitar synthesizer system. It has humbucker pickups, controls for the synthesizer system and a sustain bar connecting the body to the headstock. It appears in the Girls & Boys video and there are eyewitness accounts of it in the studio for the Sign O The Times sessions.
The guitar synthesizer system was first used during the Parade sessions. It can be heard on Girls & Boys, Sexual Suicide and Anotherloverholenyohead (the "duck" sound). Wendy also used this guitar live on the Parade tour and plays it in the Girls & Boys video. There is an eyewitness account of Prince using the guitar for the Sign O The Times sessions, but it is unknown where on the album it features. It was not taken on the Sign O The Times tour and there is no record of its use on later albums or tours. The whereabouts of the G-707 are unknown.