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. Delay effects range from a subtle echo effect to a pronounced blending of previous sounds with new sounds. Delay effects can be created using tape loops, an approach developed in the 1940s and 1950s; analog effects units, which were introduced in the 1970s; digital effects pedals, introduced in 1984; and audio software plugins, developed in the 2000s.