The delay effect is among the earliest and most prominent of electric guitar effects. Though it was originally experimented with in the studio by Les Paul using a reel-to-reel recorder, delay has since been manufactured in both analog and digital pedal forms for stage performance. Now it is one of the most beloved tools for guitar players, used to do everything from fatten up a solo to create futuristic ambience.
Delay Types and History
Tape Delay/Echo- The original delay or “echo” effect was produced using a reel-to-reel recorder. Sounds were recorded to magnetic tape at one head and played back at another. Multiple playback heads could be stacked for more delays The distance between the two heads and the speed of the tape set the time between each repetition. Interestingly, the minor variations in the mechanics of the machine led to alterations of the repeated sound that guitarists and engineers found desirable. This led to the “slapback” delay effect used by rockabilly guitarists.
In 1953, music store owner Ray Butts began manufacturing a combo amplifier with a built-in tape echo device called the “EchoSonic.” It was soon being used by Chet Atkins and Scotty Moore to get the tape echo effect during live performances.
Analog Delay- In order to make delay effects more portable, pedal manufactures began producing devices using solid-state circuitry in the 1970s. Analog delays use a “bucket-brigade” device to send the analog signal through a series a capacitors. The speed at which they pass through the capacitors sets the delay time. As a by-product, the signal is distorted slightly on each repeat, an effect favored by many players. One of the best and easiest to use analog delays is the MXR Carbon Copy.
Digital Delay- This delay type works by sampling your analog signal, converting it into a digital signal, holding it for a set period of time and then re-introducing it into the original signal flow. Digital delay allows for much greater delay lengths than analog delay plus the ability to “tap” in a delay time, but many players consider the digital re-productions harsh compared to analog delay. They make great options for looping and producing delays at set rhythmic intervals. One of the most popular digital delays is the Boss DD-7.
Common Delay Controls-
Most delay pedals will have three main controls, though manufacturers sometimes create their own names for each.
Delay- Set length of delay
Feedback- Set amount of repeats
Level- Sets volume of each repetition
Common Delay Pedal Settings-
Doubling- Setting a minimally short delay time with a single feedback and the level at or near maximum repeats each attack so quickly and similarly that the combined signal mimics two guitar playing at once.
Delay- 20-50 milliseconds
Feedback- 1 repeat
Slapback- To emulate the original tape echo effect, analog delay can be set to a relatively short time with a single repeat and a decay in volume,
Feedback- 1 repeat
Ambient/Reverb– Delay pedals can also be used to get the reverberation effect of a sound echoing within a room. This technique is highly customizable to the size and depth of reverb the player desires.
Feedback– 3-5 repeats
Delay to Specific Rhythms- Using a digital delay pedal where the delay time can be set in milliseconds and a bit of math, we can set the delay length to a chosen rhythmic value for a given tempo. The easiest way to do this is divide 60,000 (the number of milliseconds in a minute) by the tempo of the song in beats per minute (BPM) to get the amount of milliseconds per beat.
IE for a tempo of 120BPMs:
60,000/120=500ms per beat
To get a specific subdivision, multiply by:
16th-Note Triplet: .166
8th-Note Triplet: .33
Quarter-note Triplet: .667
Dotted Eighth: .75
Quarter Note: 1
Dotted Quarter: 1.5
Half Note: 2
Dotted Half: 3
Whole Note: 4
Delay Pedal Placement- Since delay itself has no effect on the signal, its recommended placement is at the end of the chain. Distorting or modulating a delayed signal can lead sounds to bleed into one other, so distortion, wahs, EQs, chorus, phaser, etc., pedals are generally placed before them. As such, if you are primarily using distortion from the amplifier, it is customary to run the delay pedal out of the effects loop (the 1/4 inch output/input on the back of the amp). While these configurations are common, guitar players have been known to experiment with alternate pedal orders to get a desired sound.