Being some of the most important effects that can be applied in electronic music, reverb and delay (sometimes called echo) are two methods of signal processing. Often, these are incorrectly confused. Actually, this confusion is understandable since it mainly comes from the fact that both effects are closely related. Indeed, both reverb and delay create a presence, making a sound thicker and more noticeable in a track than it originally is.

This article contains excerpts of Rick Snoman’s “The Dance Music Manual (3rd Edition)”.

I. The basics of reverb

1. Definition & different types of reverb

Reverberation is a term used to describe the natural reflections a person expects to hear in different environments and provides essential auditory clues as to space, furnishings and general structure.

In music production, to create some depth and natural space within a dance mix, the producer must employ artificial reverberation.

Two types of artificial reverb exist. These are convolution and synthetic reverb. Whilst you don’t often hear about convolution reverb, it is a type of reverb that relies on samples to reproduce real acoustic spaces accurately. Their main advantage is they are realistic. However, their main downfall is that youth don’t come with great customization options.

In modern-day music production, synthetic reverb is more commonly used. As opposed to convolution reverb, synthetic reverbs rely on algorithms to determine how certain acoustic spaces would react to a sound source.

Most of the times, a careful mix of both convolution and algorithmic reverbs are used within a production. However, whilst the process of reverb seems straightforward, its key elements suggest the there is more than meets the eye to it.

2. Key elements of reverb

1. Ratio (mix)

In a reverb unit, this corresponds to the amount of reverberation that is applied to a sound.  More ration will translate into more reverberation than direct present sound. Less ratio will result in more direct sound than reverb.

2. Pre-Delay Time

Pre-delay time is the time separation between the direct sound and the first reflection. Often, this parameter will be represented in milliseconds. It determines the time differential between the original sound and the perception of the first sonic reflections.

3. Early Reflections

Usually, this type of parameter is only featured on high-end equipment. It enables control of the sonic properties of the first few reflections of a sound.

4. Diffusion

Directly related, diffusion is a measure to determine how far the early reflections spread across the stereo image. The positioning of the listener will determine the amount of stereo width that is perceived in those early reflections.

5. Density

An original signal will continue to reflect off different surfaces after its early reflections. This corresponds to the reverberant field. You can control this field on a reverb unit by the density parameter.

6. Reverb Decay Time

This parameter corresponds to the amount of time the reverb will take to decay away. By increasing the decay time, the producer can effectively increase the size of the ‘room’.

7. HF and LF Damping

The further reflections have to travel the less high-frequency content they will exhibit due to absorption through air. By reducing the high-frequency content (and reducing the decay time), the producer can create the impression that the sound source is occurring in a small enclosed area with soft furnishings.

II. The basics of Delay

1. Definition and different types of delay 

Delay can be defined as an incoming audio signal by a predetermined time that is commonly referred to in milliseconds or note values.

The amount of delays that are generated are termed the feedback, thereby increasing the feedback setting, it is possible to produce a multitude of repeats from a single sound.

2. Key elements of delay

As with reverb, delay can make a sound wider, more present and more dynamic over time.

Some delay units are more specialized than others in the parameters they provide. Usually, delay until offer delay times, and the possibility to delay the sound or the left or the right or pan them to the left or the right of the stereo image.

Sometimes, pitch shifting may be included, filters to modify the harmonic content, distortion, groove adjustments or an LFO. All these modify the characteristics of the sound and perceived rhythm.

III. Reverb & Delay Tips From: “Music Habits: 101 Production Tips for Computer Musicians”

1. Reverb tips

  • It is not unusual to follow a reverb with an EQ unit, letting you further sculpt a reverb tail with EQ.
  • Reverb can be used to help give your track a greater rhythmic impact. The trick is to adjust the decay of the reverb to fade out right before the next 1/4 note (or 1/2 note) comes in.
  • Use a predelay to give your instruments dimension while not losing the clarity, or as an interesting delayed sound. Works great with drums.
  • For most sounds you add reverb to, you’ll want a highpass filter to remove low-frequency reverb. You want to keep those low frequencies as clean as possible.
  • Reverse reverb can be a really cool effect and it’s not hard to do. Simply reverse a sound. Apply 100% wet reverb to the reverse sound. Render the resulting sound. Re-import the sound as a layer to your original sound.
  • Reverb plays a huge role in giving your song dimension & depth. By using different settings for certain instruments, you are able to make some things appear close (little to no reverb) to sounds that appear distant (longer reverbs, bigger rooms). It’s a good idea to set up multiple send/ return tracks with reverbs specifically dialed in front, middle and rear of your mix.

2. Delay tips

  • Adding a subtle triplet delay to a simple melody can create more depth and complexity while adding to the overall groove. Works great for percussion too.
  • Replacing some of your reverbs with delay can help clean up your mix as delay is less dense. The delays should be a straightforward 1/4 note or 1/2 note instead of an unusual timing.
  • Like reverb, it’s best to remove the low frequencies of your delays to keep your mix sounding clean.
  • Experiment with putting the delays wet/dry above 50% to create odd but sometimes very interesting timing changes of your parts.
  • A long delay followed by a filter with an LFO sweeping frequencies can create great atmospheric extras to your music. This works best as a send/ return track. You’ll also want the low frequencies removed.

IV. Common Reverb and Delay Mistakes

Most of the time, an inexperienced music producer will make the same mistakes with both delay and reverb. That is, applying these effects on sounds which they don’t have to be applied (kicks, sub-bass frequencies) except if it is the desired effect.

For example, you wouldn’t use reverb on a kick unless you use it for a more effective breakdown.

Another example is delay with sub-bass frequencies. Delay should (almost) never be used with sub-bass frequencies.

Moreover, not all instruments should be treated to the same amount or style of reverb, and careful consideration must also be given to any number of factors from sound design to acoustic positioning.

Putting both too much reverb or delay will wash away your sound. Except if it is a wanted result, you shouldn’t employ both of these effects without precise goals.

V. The Effective Implementation of Reverb & Delay: Track Analysis

Throughout this Lapalux track, you get an unprecedented sense of space. The Essex-based producer clearly knows how to compose memorable melodies and beats. Often, this feeling is emphasized through astute processing and application of effects. In this particular track, you really get the feeling that reverb and delay play a preponderant role in creating a certain atmosphere for the listener. The filtered arpeggiator at the very beginning of this track heavily relies on reverb, and the marriage between unforgettably spaced out vocals and an endless buildup help creating an even more memorable drop.

In a similarly experimental track, Oneohtrix Point Never provides a fantastic immersion for the listener. What seems to be a vocalized pad accompanies the listener throughout the track until an unexpected drop. Samples of what seems like a police siren, a telephone and the development of the original melody make this track a true classic. Once again, it is the combination of reverb and delay in the build-up which allows the creation of this grandiose impression and scheme of sounds.

Reverb vs Delay Conclusion

Delay and Reverb play a predominant rule in music production. Think of food without salt, pepper or spices. It doesn’t taste that good. With reverb & delay it is the same thing. Any track would sound dull or unfinished without the appropriate amount of reverb & delay added to it. However, it is only though practice and experimentation that you can develop a good ear for what sounds right.

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