Audio Effects: Delay

The delay, or echo effect is a widely used effect that can simulate the echos of a canyon or the close audible reflections of a music venue. This effect is also useful for creating a sense of space for the listener and has several useful control settings. If you have ever shouted into a large space or canyon and heard your voice return to you shortly afterwords then you have heard the natural effect of delay. This effect can be recreated in a studio environment by the use of a small stomp box or an elaborate rack system that contains several other effects.

The delay effect was actually discovered by accident when recordings were made with magnetic tape. Once the tape was spooled onto the receiver roll the tape would be resting on the footage that was spooled just before in a continuous loop all the way to the end of the tape. In some cases the magnetic properties of one section of tape would “bleed” onto another section that it was directly in contact with and this would cause a ghost image of the first audio section to be transferred to the second audio section. This would create a slight delay effect and so the use of this effect was born.

Initially this was considered to be a mistake or a defect in the recording process but later was considered to be an enhancement and the tape loop delay system was developed for use in the studio. Now the delay effect can be created electronically or by using software that recreates this widely used and common studio effect. Delay is a different effect than reverb as delay effects will literally delay the original signal and return it in tact later a reverberation effect will return a constant blend of all sounds in the form of an audible drone.

A basic delay effect system will have a set of control knobs that can be adjusted to fit the parameters desired by the artist or audio engineer. These control parameters are most commonly called “Delay Time”, “Feedback” and “Level”.

Delay time is the amount of time the original audio signal is held in silence before it is released and played back after the original signal has begun. This is the echo parameter of the delay effect. An example would be to shout your name into a canyon and set the delay time parameter according to the size of the canyon and distance to the far wall of the canyon. The larger the canyon is and the distance of the reflecting wall of the canyon will determine how long it takes for you to hear your voice after you shouted your name or the commonly used “hello”.

The feedback parameter is used to set how many times you hear the “hello” being returned. At high damping levels you might only hear a single “hello” while setting this parameter to its highest setting can create an infinite chain of “hello” that repeats over and over again.

The level parameter is the volume of those echos that are repeated and can be set at the original signals level or set to fade slightly on each echo until in fades into silence.

A delay can also be used to play an instrument part while you play a lead over it or some other progression. The way this works is you would play a chord progression on a guitar and record that progression on the delay system. Once you have this timed correctly you can trigger what you have captured and have the delay repeat that chord progression indefinitely while you play a lead break over the top of the delay effect. There are several unusual ways to use this effect and there are several different styles that can be implemented but the basic parameters are usually the same. The delay effect is a common and widely used audio effect and can be heard on a daily basis in commercials, music and movie sound tracks.