Delay is one of the most powerful tools at the disposal of any musician or audio producer. It’s a classic effect that is extremely versatile, plus it just sounds really cool.
But what exactly does delay as an effect do to our audio? We’ve all stood in a large empty room or maybe at one end of a canyon and yelled “hellooooo!” and heard the sound repeated back at us a short time later.
While that “real world” method really combines both delay and reverb, in essence, a delay is when an audio signal is played, stored in some sort of medium, and then played back after a certain period of time.
The technology for delay as an audio effect originated with the use of tape loops as early as the 1940s, and some artists used primitive delay effects (most notably “slapback” delay) throughout the 1950s. But it was really the Beatles and other artists in the 60s that made it so recognizable as they were able to incorporate it into the popular music of the time in so many new ways.
Delay further evolved throughout the 1970s and 80s thanks to the rapid technological advances of that era. Even in the 2020s, it is still being refined and expanded upon as CPU and RAM specifications continue to improve.
So, we know that delay is extremely useful. But it can also be really easy to abuse and create an echoy-and smeary mess. It’s important to understand both how delay effects work and how different types of delays can give you access to a wide palette of sounds.
Tape vs Analog vs Digital
There are 3 main types of delay that you can use in music. Each one has a different “character” with different advantages and disadvantages. In general, the differences between each delay type can be heard in the initial echo and delay trails (feedback or repeats).
1. Tape Delay
The earliest method was known as tape delay, which – as you can tell – involved magnetic tape. Essentially the tape would record your signal then pass through a playback head a short time after. This means you hear your initial sound as you play it, and then an “echo” as it hits the playback head.
Naturally, tape is kind of annoying to manage. These systems were bulky yet delicate thanks to the numerous sensitive mechanical and electrical components. Tape delay machines were – and still are – quite expensive and hence out of reach for many musicians.
With that being said, they sound awesome, and some of the most famous musicians from the 1970s (like Brian May, David Gilmour, and Jimmy Page) used the EP-3 Echoplex Tape delay unit to craft some of their most well-known sounds.
There’s no single tape delay sound – every unit is different. But if it had to be generalized, think warm and lo-fi with feedback trails that get progressively more distorted. Tape delay machines are not known for being “precise”. You can expect to encounter pitch wobble, noise, and other analog idiosyncracies.
Other famous tape delay units include the Roland RE-201 Space Echo, and the Binson Echorec, Tape Echo is commonly associated with guitar effects, but can also be used on any source that you want to have a sort of “vintage” grittiness to its delay sound.
Tape delay is also heavily featured in dub and reggae music. These genres simply would not exist without delay – you would not have the characteristic “warm” dub sound without tape delay specifically.
Because tape delay was relatively costly and hard to maintain, people started to develop new methods to create the sounds of a tape delay, and so-called “analog delay” units and guitar pedals were born.
Initially, these were designed to provide more portable and “sturdier” alternative for guitarists looking to get the sounds of their tape delay units without all the expensive maintenance on the road.
These pedals use a “bucket brigade” circuit to achieve delayed sounds. This aptly named circuit uses a series of capacitors. Each capacitor takes a small sample of the signal and passes it along to the next capacitor, much like a real-life “bucket brigade” does with a pale of water.
When this signal is mixed with your original sound, you get a delay effect that is similar to a tape delay, but not exactly the same. Most notably, bucket brigade analog delay effects are typically much darker sounding than a tape delay, mainly because the bucket brigade circuit needs to be low pass filtered to preserve the quality of the sound.
While there are plenty of analog delay pedals that feature bucket brigade circuits today, you can’t technically have a true “analog” delay that features a fully analog bucket brigade circuit. This is because the bucket brigade circuit “samples” the voltage in a way that is not a true representation of the input. It’s similar to digital sampling, but with voltage instead of bits.
This process also causes the sound to sound significantly “filtered,” which can be really useful but it isn’t necessarily a clean sounding delay either.
Bucket brigade circuits were also pioneering in the effects realm because they are able to accurately recreate shorter echoes than tape delays, which makes them much more suitable for both “slapback” delay sounds and for use in chorus and flanging effects.
3. Digital Delay
The last common type of delay is a digital delay. These effects started out as rack mount studio effects in the late 1970s into the 1980s and feature the “cleanest” sound and operation.
In DSP, creating a delay of a sampled signal is a very simple operation, and the overall “quality” of the signal is really only affected by the quality and speed of your sample rate and A/D conversion. Today, there are loads of digital delay plugins you can use in your DAW. Many plugins aim to recreate bucket brigade and tape delay systems, making them somewhat of a hybrid despite being fully digital.
Other Types Of Delay
While the above types of delay largely represent the most common methods of achieving delay sounds in music, there are plenty of other less common methods out there.
These different “types” of delay are all usually based around the principles found in the three major types, and can all be created with delay units of the above 3 archetypes.
Slapback Delay/Echo is a short, single repeat echoed effect that was commonly used in the 1950s in Rock and Roll as a vocal and guitar effect.
Because the short delay time adds extra energy and excitement, it’s a fantastic trick for drawing attention to a sound. The single repeat means that it doesn’t create a big washy trail behind you as you play.
Slapback sounds are typically found in faster tempo songs thanks to its energetic nature. It’s best to use tape or analog delay to create a slapback effect as it gives you that all-important vintage character.
Here are some settings you can try for slapback delay:
Delay time: 75 – 250 ms
Mix: Above 50% wet
Modulation: None or subtle pitch modulation
A doubling echo is an effect that is designed to replicate the sound of double-tracking with a delay.
This type of delay doesn’t actually produce noticeable echoes, but rather adds a doubled or thickened quality to the sound. There aren’t really any “specific” settings for creating this aside from a very short delay time, typically 30-50ms.
The rest of the settings are usually very dependent on the source material, so it’s best to set them by ear. While this method does “replicate” double-tracking, it does sound noticeably different and is somewhat less accurate than proper double-tracking.
It can be achieved with any delay style, but typically, analog delay with light modulation or clean digital delays create this sound best.
Sample settings for doubling echo:
Delay time: 30 – 50 ms
Feedback: Depends on source material but typically shorter
Looping delay, as the name suggests, is functionally a looper set up using a delay. Originally tape delays could be used to create this “looped” sound, where entire phrases of sound would be repeated in a tape loop that you could then play a harmony or other complimentary sound over.
This was further expanded upon with digital delays in the 1980s and eventually led to the creation of dedicated loopers as we know them. A looping delay can be thought of as a looper without dedicated record or playback controls, so you are somewhat at the “whim” of the delay time and feedback controls. These types of delays are common in modular synthesis as they allow performers to create many different layers of sound with ease.
Modulated Delay can be thought of in two different ways:
First, tape echo and analog delay effects naturally apply some amount of filtering or modulation to the signal due to the nature of their designs. By using more extreme settings with the modulation, you can create some otherworldly and interesting effects.
Most analog and tape-style delay effects have modulation controls, which will blend in any one given effect (sometimes this is chorus, or vibrato style effects) to emulate that tape degradation warble sound.
The second approach to “modulated delay” effects is to simply combine a delay with a chorus, flanger, or phaser (or any other type of modulation). You can experiment endlessly with combining different modulations to the dry signal before it hits the delay unit, or even loop the modulation on the input so it only affects the repeated signal.
Chorus and delay can add extra width and energy to a delayed signal, keeping it to the front of your mix, while flanging and phasing can introduce cool artifacts and movement across your mix field.
You can even feed a delay into another delay to create complex poly-rhythmic delays. This is a basic type of multi-tap delay, which is another sub-type we’ll look at in a moment.
This is basically a “network” of two or more delay lines (or taps) which can be arranged in any number of ways. Multitap delays are almost always digital due to their complex nature.
Even with just two taps, there are a number of various ways they can interact with the input as well as each other. Maybe the audio goes into the first tap, then into the second one, but only the second tap has feedback. Or maybe the audio goes into both taps at the same time in parallel and the result is mixed together. Once you start adding in more taps, it’s easy to see how vast the possibilities are.
Multitap delay can even be used for reverb-type effects, particularly if each tap has modulation and filtering to assist with diffusion. You will certainly need a lot of taps for anything realistic, but I would suggest this is missing the point. If you want reverb, use a reverb plugin (here’s a list of free reverb VSTs). But if you want a unique reverb-type effect, you can mess around with multitap delay.
Ping Pong Delay
Ping pong delay sounds as if the echoes are bouncing from left to right.
What’s happening here is the input sound only enters the delay on one side – in Ableton’s Delay effect it’s the left channel. Then the delayed signal is fed back into the delay tap on the other side. This process is repeated so that each successive echo alternates from left to right.
This may not be the only approach you’ll encounter, for example even if the input feeds into both channels but the feedback still alternates this will sound different from a traditional delay effect.
It’s usually a feature found on delay units, it’s rare to find a plugin or hardware device that is fixed to ping pong mode.
It’s a really cool trippy effect but can overwhelm the stereo image. I would recommend using short, simple sounds with ping-pong delays. You can let the repeats from the delay effect become a part of the instrument, providing a wide but clean decay to a sound that is otherwise abrupt.
Dub and reggae artists also frequently make use of ping pong style delays for drum processing. Running hi-hat patterns through a rhythmic ping-pong effect can really spice things up and add width to the top end of your mix.
Dub delay was invented for the style of music it’s named after, Dub. Dub delay is a somewhat complicated effect, typically consisting of multiple effects chained together to give that signature sound, but there are a few common “style” parameters that can get you close.
Dub music has its roots in the sound system culture of Jamaica in the late 60s and 70s. Most pioneering dub artists were using what was considered “old” equipment at the time, which means tape delays.
The “gold standard” for dub and reggae delay effects is the Roland Space Echo, but really any tape delay effect will get you close.
Typically as the delay feeds back, it sounds more and more distorted. It’s an irresistible effect that you’ve no doubt heard countless times. Most modern dub delay type effects have filters in the feedback path to make things sound more “distant” with each repeat.
Dub delay effects are quite musical – when you play with the delay time and feedback, you can expect the sound to adjust in a way that is free of clicks and glitches.
Although it’s hard to adjust the delay time on any unit in a transparent way, the pitch modulation effects you get with dub delay are very exciting and can be used for all sorts of sound effects. You should also be able to modulate the delay time subtly for classic “tape flutter” effects.
How To Calculate Delay Time
With all time-based effects, it is often very useful to sync up your delays to the tempo of the song.
This is easy with plugins because they can read tempo information from your DAW. But if you’re dealing with hardware, you’re going to have to do this manually.
Many hardware delays and guitar pedals feature a “tap tempo” button that allows you to set the tempo of the delay by tapping in rhythm to the music. This is super convenient in a live sound setting where there might be tempo fluctuations or where you can’t determine the starting tempo.
However, some units only display their delay in milliseconds (ms). This doesn’t mean you can’t calculate the proper delay time though! Here’s a nifty thing to remember:
Divide the number 60, 000 by the BPM of the song to get the ms value for a 1/4 note delay.
So at 120 BPM this value is 500 ms. This means in a song at 120 BPM, each beat is 500 ms apart.
Using that equation, you can also pretty easily determine that:
If you half the 1/4 time, you’ll get a 1/8 note delay, and if you divide that number again you’ll end up with a 1/16 delay.
If you want to add some easy syncopation, you can use a dotted delay time. To calculate the dotted time, just multiply any of the above results by 1.5, and if you want to create a triplet delay, multiply any calculated value by .667.
You can use these formulas in a pinch if you don’t have a delay with a tap button available, or if the project you’re working on isn’t lined up to a grid in your DAW.
One final note about delay time, while it is important to sync things up so that they sound in time, some delay effects like slapback or doubling should not be synced to the tempo of the song and should be kept short. And since slapback and doubled effects are so short and only feature 1-2 repeats anyway, you won’t have to worry about it messing with the rhythmic structure of the song in a major way.
Echo and Delay are largely used interchangeably in the audio world, both in terms of labeling effects and with their function. In reality, they are somewhat different.
Echo is truly a subset of delay as a whole (kind of like the difference between a square and a rectangle). It’s a little more sophisticated and “thicker” than a bare-bones delay effect, with added filtering, overdrive, and sometimes reverb.
I like to describe delay as a building-block effect. It sounds good on its own but can be duplicated multiple times or modulated in various ways to produce a huge range of other distinctive sounds. You could say echo is a sound that delay can make.
Delay Control Parameters & Terms (A Glossary)
Every delay device, plug-in, etc will typically feature some of the following controls, but also know that any delay will sometimes have its own terms for what these controls all do. So you should always consult your product or plug-in’s manual if you are unclear about any control!
Time, Delay, or Rate
This typically controls how much time there is between each repeat. Digital delays can have the longest delay time, while tape and analog delays are shorter. Long delay times create polyrhythmic and looping effects. Very short delay times create slapback, doubling, or comb filter effects.
Mix or Level
This controls how strongly the delay effect is mixed with your original signal. Ideally, if you set it to 100% wet you will only hear the delayed sound. This is useful when using multiple delays in parallel or on a return channel.
Feedback or Repeat Time
Each successive echo is fed back into the input of the delay pedal, creating a “repeating” effect. These controls change the intensity of each repeat, making it possible to have subtle trails or full-blown psychedelic madness as the feedback builds up.
Most pedals, especially digital ones, will allow you to create loops when the feedback is pushed to 100%. Emulations of tape delay often apply overdrive here, allowing you to create dub-style echoes.
Many analog and tape delays feature some sort of modulation control, which is designed to emulate the wow and flutter effects inherent in tape machines. However, many modern pedals take this to new heights with full-featured vibrato or chorus style effects built into the delay.
(Now that you’re an expert on the different types of delay, check out our comprehensive reverb cheat sheet that covers everything from different reverb types to the best settings to use for drums and vocals.)