Reverse echo

Reverse echo or reverse reverb, also known as backwards echo and reverse regeneration, is a sound effect created as the result of recording an echo or delayed signal of an audio recording played backwards. The original recording is then played forwards accompanied by the recording of the echo or delayed signal which now precedes the original signal.

Guitarist and producer Jimmy Page claims to have invented the effect, stating that he originally developed the method when recording the single "Ten Little Indians" with The Yardbirds in 1967. He later used it on a number of Led Zeppelin tracks, including "You Shook Me", "Whole Lotta Love", and their cover of "When the Levee Breaks". In an interview he gave to Guitar World magazine in 1993, Page explained:

Later, when we recorded "You Shook Me", I told the engineer, Glyn Johns, that I wanted to use backwards echo on the end. He said, "Jimmy, it can't be done". I said "Yes, it can. I've already done it." Then he began arguing, so I said, "Look, I'm the producer. I'm going to tell you what to do, and just do it." So he grudgingly did everything I told him to, and when we were finished he started refusing to push the fader up so I could hear the result. Finally, I had to scream, "Push the bloody fader up!" And lo and behold, the effect worked perfectly.

Despite Page's claims, an earlier example of the effect can distinctly be heard towards the end of the 1966 Lee Mallory single "That's the Way It's Gonna Be", produced by Curt Boettcher.

Reverse reverb is commonly used in shoegaze, particularly by such bands as My Bloody Valentine and Spacemen 3.

Reverse echo has been used in filmmaking and television production for an otherworldly effect on voices, especially in horror movies.

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