Roland GS-500

The Roland GS-500 guitar was a guitar controller designed for the Roland GR-500 guitar synthesizer in the late 70s, with Roland Humbucker pickups, a Les Paul-style body and a "honeyburst" finish. However, unlike later guitar synth controllers, its output jack was not of the standard 1/4-inch size so it couldn't work as a guitar on its own.

Andy Summers got one alongside the GR-500 from Manny's, around Spring 1979, and first used both on the Reggatta De Blanc album. The GR-500 was used for faint bubbling noises on "Walking On The Moon" - probably achieved via the guitar's sustain (from built-in magnets in the main body).