How a grand piano, Leslie speaker, and tape delay created the iconic 'ping' in 'Echoes'

The signature “ping” that opens “Echoes” wasn’t a synth or a prepared guitar — it was a single note from a grand piano, run through a Leslie rotating speaker and then slowed down on tape. Engineer John Leckie, then a young tape-op at Abbey Road, was asked to help the band get a weird, watery sound. David Gilmour played one note, and the Leslie’s Doppler effect gave it that warbling swell.

The band then used a Binson Echorec tape delay to repeat the note in rhythmic bursts. By manually adjusting the delay time and the tape speed, they locked into the hypnotic sequence that became the song’s spine. Leckie later said the whole thing was a happy accident — they were just messing around in Studio Two, trying to make a sound that hadn’t been heard before.