
Delay (audio effect)
Delay is an audio signal processing technique that records an input signal to a storage medium and then plays it back after a period of time. When the delayed playback is mixed with the live audio, it creates an echo-like effect, whereby the original audio is heard followed by the delayed audio. The delayed signal may be played back multiple times, or fed back into the recording, to create the sound of a repeating, decaying echo.[1]
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 and used by artists including Elvis Presley and Buddy Holly.
Analog effects units were introduced in the 1970s; digital effects pedals in 1984; and audio plug-in software in the 2000s.
Artistic uses[edit]
In popular and electronic music, electric guitarists use delay to produce densely overlaid textures of notes with rhythms complementary to the music. U2 guitarist the Edge uses delay while he plays arpeggios on electric guitar, thus creating a sustained, synth pad-like background.[31] Vocalists and instrumentalists use delay to add a dense or ethereal quality to their singing or playing. Extremely long delays of 10 seconds or more are often used to create loops of a whole musical phrase. Robert Fripp used two Revox reel-to-reel tape recorders to achieve very long delay times for solo guitar performance. He dubbed this technology "Frippertronics", and used it in a number of recordings.[32]
John Martyn was a pioneer of the echoplex. Perhaps the earliest indication of his use can be heard on the songs "Would You Believe Me" and "The Ocean" on the album Stormbringer! released in February 1970.