How the Rolling Stones Used a Leslie Speaker to Make 'She's a Rainbow' Swirl

On Their Satanic Majesties Request, the Rolling Stones wanted a psychedelic sheen for “She’s a Rainbow.” Engineer Glyn Johns came up with the idea of running the entire string section and piano through a Leslie speaker—the rotating cabinet normally reserved for Hammond organs. The spinning internal horn and woofer created a Doppler-like pitch shift that made the orchestral arrangement sound like it was breathing and circling around the mix.

The effect was so extreme that the string players had to overdub their parts to a click track while monitoring the warped playback. The piano was also run through the same Leslie, giving it that dreamy, unsteady warmth. The result was one of the band’s most unique sonic textures, blending classical orchestration with the kind of analog hallucination you’d normally only hear on a psychedelic rock record.