Creative Uses of Common Effects: Delay/Echo

Delay is a fantastic effect in music. It is used throughout many songs and is both naturally and unnaturally occurring. Consider the simplest delay, an echo, a drum plays in a large room and shortly after hitting it, the sound is heard again, after bouncing off the wall. For many applications, playing with simple reflections is all you need to turn a delay into a creative tool, but there are many more options out there.

Many people often ask what the difference between an echo and delay is. Simply put, they are the same. Echos are natural reflections, a delay is the studio mimicry of an echo, created by delaying a signal and then playing it back shortly after the dry signal is played.

So how can we use delay? Firstly, and most simply, we can use it to define the size of a room we want the listener to "be" in. I've lifted a video from Youtube which perfectly demonstrates this:

Especially when combined with reverb, the delay function is the most essential tool to place the listener in the desired environment. 

It is used to extra beneficial effect in reverb plugins on a control normally called "pre-delay" which is the delay prior to which the reverb kicks in. This simulates the time taken from the sound, for the first echo (of the thousands of echoes) which makes up the reverb.

It can be placed on lone instruments in the mix, to push them further back in the room, and the absence of such, in an otherwise delay and reverb dense mix can bring a sound forward. This technique is often applied to vocals and backing vocals to gain a separation.

The second technique I will show you is essential to many guitar players styles. The rhythmic, tempo-locked delay. 

By echoing the notes you play, you can "play" more notes at once. If your melody uses quarter notes and you put on an eighth note delay, in between every note you play, will be an echo. 

This increases the energy of the track as more notes are heard. It also makes the melody sound a lot more complex. Try and play about with triplet delays too, adding different feels to the original style.

This is well demonstrated by this guitarist:

This trick may be useful if you have a monophonic synthesizer or instrument and want to play chords. By arpeggiating a chord, and having the delay time to be the note intervals, each note in the arpeggio will repeat as you play a new one in the triad.

There is one control which is important to get the hang of, else your delays could become a major issue in the mix. Feedback takes the delayed signal and mixes it back into the input to be delayed again. It is usually mixed in at a lower volume each time so that the echo tail eventually fades but a cool trick is to temporarily put it above zero dB.

THIS IS DANGEROUS IF DONE WRONG as the volume will keep increasing so always be ready to turn the feedback down below zero dB before you get such an incredibly loud signal that you start a fire or damage your equipment.

I do this for a few bars maximum with a limiter on it and it generates a cool effect. The limiter crushes the volume down, meaning at various points in time different parts of the signal are expressed, be careful though, as even the limiter won't handle super high volumes and will eventually distort (an effect you may find desirable in circumstances).

Delay can also be used to enhance the stereo scale of a track psychoacoustics allow the HAAS effect to trick the ear into thinking the sound is coming from one side. By delaying the signal in one ear, the brain perceives this difference as the extra time taken for the sound to travel the distance of the skull and applies a directional element to the sound.

Ping-Pong effects do this well too, by having multiple delays at different timings, each hard panned to alternate ears, to get an effect similar to that standing at the side of a ping-pong table.

This effect can be good when increasing energy for builds too (click the link for relevant article).

Delays, therefore, are extremely powerful for both conventional and unconventional uses. By applying some theory and understanding, you can generate "impossible" and unnatural sounds that can thicken up your mix. Care must be taken however as there is much scope for damage to the track and potentially equipment if applied incorrectly. Good mixing skills are a must in addition as these sounds can often stray wildly and you want complete control of them to make them work.