Delay (audio effect)

A delay is a propagation delay that is in music production at the Laufzeitstereofonie than Predelay the reverberation, as Haas effect occurs in public address systems and sound design used in a targeted manner.


The sound effect can spend one or more delayed copies of the input signal, and it thus creates an echo -like sound. A delay can be achieved both by an electronic component as well as with the aid of software. An electronic delay effect can be generated by an analog circuit, a digital algorithm, or a tape device (see Hall device).


A delay arises from the fact that the direct sound with respect to the audio signal recorded with the microphone, amplified and reproduced via loudspeakers is delayed. This phenomenon occurs only in larger rooms on distributed speakers. The result is a deficit of localization, because the human brain is the source of there locates where the sound comes first ( direct sound ), see precedence effect. Since in this case the loudspeaker and not sound source corresponding delay ( delay ) must be set. Often the various delays are matched to the respective speaker groups such that the (natural ) sound from the speaker as much as 20 ms arrives earlier near the stage in the rear audience area. It should be noted the necessary Haas effect with a delay of 20 ms ± 10 ms, and the echo detection threshold of about 50 ms at the same level of direct signal and reflection. Even with video -assisted events, the transferred image with a corresponding delay is provided to ensure synchronicity of visual and auditory perception.

Tape Delay

Tape Delay is the use of run- time differences of the tape between record and playback head for reverb and echo effects. The signal from the playback head of the tape machine is applied to the recording head back out (feedback), then an echo -like repetition of previously recorded sound event with a time lag corresponding to the distance covered by the band between the recording head and arranged for him reproducing head. Moreover, the feedback signal is continuously changed by the multiple and copying generation loss effects in quality with respect to linearity and harmonic distortion frequency or " deteriorated ".

The method has been 1951 to hear from Les Paul in his home on January 4, 1951 with Mary Ford How High the Moon recorded for the first time. Guitarist Les Paul was also an innovative recording engineer who has contributed to the development of sound effects. The slap-back echo is heard for the first time at Little Walter's harmonica instrumental song Juke, taken on May 12, 1952 Universal Recording in Chicago. From 1954 it has Sam Phillips then made ​​a hallmark of his record label, Sun Records in Memphis, this did not last given the resulting here early recordings of Elvis Presley their inimitable character. He had two Ampex 350 tape recorders, their interaction generated this echo through small time delay in the same shot. The music direction " Dub" was significantly influenced by the use of delay.

Delay in sound design

A delay can also be used as a sound effect.

Some types are:

  • X - Delay
  • Stereo delay
  • Filter Delay
  • Multi-Tap Delay
  • Reverse delay
  • Modulation Delay

The key parameters for all Delay are:

  • Delay ( ms ): Delay time in milliseconds
  • Feedback (%): feedback of the output signal to the input in percent
  • Mix: ratio between original and effect signal

Sound Samples

  • Another Brick in the Wall ( Part One) by Pink Floyd (1979 )
  • Walking on the Moon by The Police (1979 )
  • Where the Streets Have No Name by U2 ( 1987)