A tape echo device records incoming audio to a loop of magnetic tape, then replays the audio over a series of several playback heads before it is erased again by new incoming audio.

Several designs exist, some with multiple playback heads, some with a sliding movable record head. This effect is easily heard on early Sun Records recordings by Johnny Cash, Roy Orbison and Jerry Lee Lewis.

This technique is still used today, and machines that are capable of it are still in manufacture, although many recording artists have opted for digital alternatives. The tape echo has a unique sound that is often imitated, but never 100% duplicated.

This can be used to achieve delay

Delay (audio effect)

Delay is an audio effect which records an input signal to an audio storage medium, and then plays it back after a period of time. The delayed signal may either be played back multiple times, or played back into the recording again, to create the sound of a repeating, decaying echo.-Early delay...

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