In the 1920’s, people started experementing with delay effects by sending audio signals back and forth through telephone lines. Listening to the original sound source and the signal coming back over the telephone line simultaneously caused the first ever artificial delay effect.
In the late 1940’s, sound engineers started to use magnetic tape decks for delay and in the 1950’s the first portable tape delays where built. Ever since then, guitar players in all styles of music have recognized