Effect: What Is It In Audio Signal Processing And When Do You Use Them?

by Joost Nusselder | Updated on:  August 23, 2022

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In audio signal processing, effects are mainly used to alter the sound of an audio signal. Effects can be used to add color and interest to a mix, to shape a sound, and to create different kinds of ambience.

From eqs and compressors to reverb and delay, there are a wide variety of effects used for different purposes within audio production.

In this article, we’ll break down the different types of audio effects, how to use them, and how to get the most out of them.

What is an effect

Definition of Effect

An effect in audio signal processing is a process or operation which changes or modifies an audio signal in some predetermined way. Effects can be used to enhance the sound of an instrument, alter another instrument, add ambience to a room, create original sounds and more.

Common types of effects used in audio production and recording include: equalization, delay/echo effects (reverb), reverberation, distortion, pitch shifting and chorus. Each one of these processes has its own unique sonic characteristics open for exploration and manipulation.

It is important to understand the concept of using effects as part of your production mix. Too little effect can seem unpolished or incomplete while too much can cause distracting coloration and unwanted masking effects on other instruments. A good balance between the two can help ensure that all instruments blend together well and give you that professional sheen you’re looking for .

Depending on style of music being produced by your project there are many different ways that effects can be applied in order to craft unique sounding mixes on any stage; from the bedroom producer all the way up to a professional studio engineer. Experimenting with each different type of effect and finding out what works best for your particular sound is an essential part of creating great music with dynamic results.

Types of Effects

In audio signal processing, effects are operations which process the incoming audio signal in some way and then output it. Effects can be used to enhance a recording or create new sounds entirely. They are used to add drama and complexity to the sound and can make all the difference between an amateur and professional mix.

Effects fall into four categories: dynamic effects, modulation effects, reverb and delay effects, filtration and EQ (equalization) effects. Dynamic processors alter the overall level of the input signal—such as compressors, limiters and noise gates—while modulation units change or modulate certain aspects of the signal, like frequency modulation or chorus. Reverb is particularly important for creating a sense of depth in a track by simulating realistic room ambience at varying levels. Delay build complex overlapping patterns that create rhythmic accents for tracks or for special effect creation.. Filtering alters frequencies by cutting away undesired frequencies which helps clean up recordings while EQ creates emphasis on selected frequency spectrums depending on preference like boosting the bass or treble frequencies.

The type of effect chosen should always reflect what is desired from each particular sound source applied to it—it takes after trial-and-error experimentation with different combinations before discovering what works best!

Signal Processing

Audio signal processing is the process of altering a signal in order to improve its sound quality or to make it more suitable for a specific purpose. Effects are used to achieve this goal, and they come in various forms and can do a lot of different jobs. In this article, we will be going over the different kinds of effects and when you should use them in audio signal processing.

What is Signal Processing?

Signal processing is the process of altering a signal, either analog or digital, in order to make it more suitable for recording, playback or transmission. In audio signal processing, effects are used to manipulate audio signals to produce certain sounds. The types of effects and their purposes vary depending on the type of signal that is being processed and the result desired by the producer.

Audio signal processors alter sound waves and usually involve methods such as frequency-based filters, dynamics processors or various time-based effects. Frequency-based processors are capable of adding subtle coloration to an audio stream by filtering out certain frequencies or by boosting them. Dynamics processors, such as compressors, expanders and noise gates enable more control over levels along with punchier musical transients. Time-based effects include chorus, delay, reverb and distortion which manipulate the natural flow of time in order to create a specific effect blending with a sound source.

When combined creatively, these different types of effects can achieve unique sonic results for all sorts of applications like music production, film post production and live performances. Signal processors have grown in popularity due to their diverse range of algorithms that allow complex sound treatments within just one device. A modern example is multi-effects processor pedalboards which usually combine multiple types of effects into one unit making them easy to use while on stage or during studio recording sessions.

How Does Signal Processing Work?

Signal processing is the manipulation of an audio signal in order to achieve a desired effect. It encompasses a wide range of techniques which are used to modify sound, including dynamic range compression, equalization, distortion, reverb, and delay. These tools can be used to enhance the quality of a recording or broadcast, or for creative purposes such as creating unique sounds or effects.

At its most basic level, signal processing works by manipulating the time-domain representation of an audio signal; this allows certain frequencies or notes within the signal to be emphasized or suppressed, and allows for more complex effects such as chorus or phasing to be created. The process of manipulating the frequency content can also generate different types of soundscapes and atmospheres when used as part of an effects chain.

The main difference between analog and digital signal processing lies in the way that signals are represented and manipulated; while analog technologies manipulate signals directly – mainly through advanced filters acting on amplitude and frequency components – digital signals are represented using binary code which must first be converted into an analog form before any processing is possible. Once again, modern digital technologies offer much greater flexibility than their traditional counterparts; they allow for much finer levels of control when it comes to adjustments such as pitch-shifting or dynamic range expansion/compression.

In addition to sound effect applications, more complex techniques such as deconvolution can be used in audio mastering processes as well – allowing engineers precise control over how various frequencies within a given mix will interact with one another – allowing them to create convincing mixes that translate well across different playback systems. In short: Signal Processing is essential when it comes to both creating music from scratch and ensuring that it translates well onto different consumer devices no matter where it ends up being played back!

Common Effects

Audio signal processing is used in a variety of different applications for altering sound. Effects are a type of signal processing that can be used to achieve this. In this article, we will take a look at some of the most common effects used in audio signal processing and discuss their benefits and limitations.


Reverb is a type of effect used in audio signal processing. Reverb can be created using a reverberation unit, also known as a reverb tank, which is an echo-producing device designed to simulate the natural reverberations you hear in indoor environments. Reverb adds a sense of depth and distance to the sound and gives it more texture.

Reverb effects come in all shapes and sizes — some use digital algorithms while others rely on physical models of real-world acoustics — but their purpose remains the same: to recreate natural sounding reverberations within an audio environment. Some of the more common reverb effects include hall reverberation, room reverberation, spring reverbs, plate reverbs, and convolution reverbs. Each type of reverb offers its own unique character and sound signature that’s tailored for particular types of applications such as recording studio vocal tracks or stadium rock music events; thus making them suitable for many different types of scenarios.

In addition to traditional reverbs, newer plugins like “impulse response” reverbs are becoming increasingly popular among music producers because they offer adjustable parameters that allow users to customize their reverb sound even further. Reverbs are often used in combination with other effects like delays and compressors to create a bigger picture when it comes to sound processing overall.


Delay is a common effect used in audio signal processing to create an echo-like effect. Delay effects use a timing element to duplicate the original sound at a later time. As the time between the delayed signal and the original signal increases, numerous repetitions will occur, resulting in a reverb-like effect.

Delays often rely on digital algorithms stored in memory and can include variable parameters such as feedback (how many times will repetitions occur), delay time (amount of time between initial sound and delayed sound), wet/dry mix amount, panning and more. Delay effects can range from shorter repeated taps of around 30 milliseconds to longer, repeating reverbs that hint towards infinity. Like Reverb, delays are commonly used for help with creating atmosphere or helping instruments fit into a mix better.

Different types of delays may also be incorporated into other effects like Echo, Chorus or Flange by introducing short delays between adjacent components within those effects. As with any type of effects processing it’s important to find any sweet spots associated with the source material in order to get the best results possible while preserving musicality of your processes sounds.


Compression is one of the most common effects used in audio signal processing. It reduces dynamic range and increases the overall volume level of an audio signal. By using a compressor, it is possible to control dynamics, sustain longer sounds and make a mix easier to listen to. There are many types of compression, from simple compressors which just multi-band compression used for more sophisticated applications.

Compressors work by reducing the difference between peak levels and the average level in a sound, which makes everything louder and closer in level during peaks in that sound. Compressors achieve this by applying gain reduction (attenuating) when audio signals exceed a certain threshold or range such as peak levels. They essentially reduce dynamic range of an audio signal so that it can be amplified more without digital distortion (clipping). It also reduces background noise while preserving the desired sound or vocal quality

Compression is most-commonly used on instruments such as kick drums, bass guitars and vocals because these instruments tend to be highly dynamic—they have significant differences between peak levels and average levels – but can benefit any instrument when used with discretion. Compression can also be used to ‘glue’ together multiple tracks by placing them at similar volumes while still allowing their stereo image to work together better in your mixdown process.


EQ is one of the most commonly used effects in audio signal processing, and it’s a vital tool for any sound engineer or producer. In its simplest form, an equalizer (EQ) boosts or cuts certain frequency ranges to make a sound louder, brighter, softer, or warmer. EQ is often used to enhance the overall sound of a track by adding detail and depth to it. It can also be used to solve certain types of problems like resonances or feedback loops in a mix.

There are two main types of EQs: dynamic and graphic. Dynamic EQs generally offer fewer adjustable parameters than graphic ones but they work far more efficiently than their graphical counterparts. They’re especially useful when used in real-time or on live broadcast signals as they can react quickly to changes within the audio signal. There are various types of dynamic EQs such as parametric, semi-parametric, phase shift/all pass, shelving and notch filters; all designed to fine-tune different frequency ranges with minimal effort on the user’s part.

Graphic EQs provide far greater control over individual frequencies when you’re mixing your song down – this type of processing is often used by professionals when further shaping the sound of their mix after all track elements have been recorded and blended together

When to Use Effects

Effects are an essential part of audio signal processing and can add depth and texture to your sound. When used correctly, effects can completely transform your audio and take it to a whole new level. In this article, we will cover when you should use effects in your audio signal processing and provide examples of popular effects that are used.

Enhancing Instruments

Using effects to enhance the sound of instruments is a fundamental part of audio signal processing. Applying effects such as delay, chorus, reverb, and distortion can make instruments sound more full and dynamic. Delay helps to thicken up sound and create depth in an instrument’s tone; chorus creates shimmer and movement; reverb adds space and dimension; distortion provides grit and attitude.

When enhancing an instrument, it’s important to keep in mind that each effect plays a role in creating the overall sonic landscape. To create the desired effect, blend multiple effects together at modest levels based on the source material being used. Trying different combinations of effects can help you find the ideal blend for your project.

For example, when crafting guitar sounds for rock or metal productions, you may use distortion for crunchy “bite” and presence; then add a subtle reverb for space; followed by some delay for echoing sustain. Similarly, for bass guitars you would likely apply some compression to preserve note definition; a bit of reverb or delay to provide ambience; then adding some low-end boost with an EQ filter to increase clarity without overly coloring the tone of the instrument.

Experimenting with different combinations of effects is essential when creating memorable tones that stand out in any mix. Don’t be afraid to try something new — there are countless combinations available in signal processing that can inspire fresh ideas when making music!

Enhancing Vocals

Vocals are some of the most important elements featured in a track and can often need to be modified and enhanced in order to achieve the desired effect. Vocals are important because they drive the emotion and mood of a song and help carry the central message or story across to listeners.

One commonly used effect in vocal tracks is reverb, which can be used to add ambiance and create a sense of space within the mix. By applying a long-decay plate reverb on vocals, you can create a lush tone that helps bring out the emotion behind each line. Additionally, an auto-pan or chorus effect can be applied on backing or harmony vocals to create swirling harmonies that accompany each phrase of the lead singer. Last but not least, using vocal doubling with slight panning on either side can help thicken your vocal stereo image, creating a fuller sound overall.

Finally, when mastering vocals it is important to avoid overhyped frequency ranges and “loudness wars” so as not to cause listener fatigue or masking effects. Instead of pushing eqs too hard and maxing compression, try setting your goal lower levels; this will achieve more clarity in your mix while still providing that competitive loudness that master engineers aim for. As always it is essential to keep an open mind when selecting processing techniques so you don’t take away from what makes each singer unique while still allowing them room around which to experiment within their own style.

Creating Special Effects

Audio effects like delay, reverb, and chorus are all useful for creating a sense of space and adding interesting characteristics to sounds. To create special effects, you can use tools such as equalization, filter and distortion algorithms, dynamic range limiter technology, noise gating systems and more.

Equalization (EQ) is one of the common tools used in producing special effects. EQ is used to adjust the frequency content of a sound by boosting or cutting certain frequencies. For example, if you want to make something sound underwater-like, you can apply an EQ with low-frequency boost and cut off the highs to create that effect.

Filters are also commonly used for creating special audio effects. Low pass filter settings remove high frequencies while high pass filter settings remove lower frequencies depending on your needs. This can be employed to emulate an amplified bass sound or a more distorted electric guitar tone. When multiple filters are used together in a chain they can create some interesting soundscapes with movement and depth that really stand out in production tracks.

Distortion algorithms often include wave shaping techniques which add crunchy characteristics to electronic sounds like synthesizers or acoustic sounds like drums or vocals. The idea behind wave shaping is that certain frequencies are increased as other ones decrease when signals hit the distortion system thus creating some unusual textures out of simple signals – these can then be further shaped with dynamic range compressors for more control over dynamics when mix balancing occurs further down the line.

Noise gating systems work by limiting the level of background noise in recordings by detecting only those parts that have significant levels within a signal’s audio spectrum; this control allows producers to keep their tracks free from unwanted noise which may take away from their projects’ quality overall.
These few examples illustrate just how varied digital audio production process is – using specialized digital signal processing tools such as equalizers, compressors, know gate systems etc., producers often design their own unique sounds and even invent entirely brand new styles while keeping within specified boundaries they find essential for their mixes’ purposes!


In conclusion, effects in audio signal processing provide a wide range of options for manipulating the sound to achieve desired results. Effects can be applied to change the timbre of an instrument, add depth and texture, or create an entirely new sound. There are many different types of effects available, each with its own characteristics and uses. Knowing when and how to use each type is essential for maximizing the desired effect on a recording. Experimentation is key in finding the right amount of effect for any individual situation – don’t be afraid to try something new!

I'm Joost Nusselder, the founder of Neaera and a content marketer, dad, and love trying out new equipment with guitar at the heart of my passion, and together with my team, I've been creating in-depth blog articles since 2020 to help loyal readers with recording and guitar tips.

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