A limiter is a device that prevents audio, digital or electrical, from exceeding a specified volume. It can be used at any volume, but it is best to operate at the maximum amplitude in order to avoid peaking.
Let me first outline the game plan before we get into detail. Let’s first define an audio limiter, then talk about its brother, the compressor. Next, we’ll explain when and how to do it.
You’ll have everything you need plus some more without having to learn technical jargon or complicated language. Let’s get started.
What is a Limiter?
A limiter can be used to process signal processing, such as mixing music. It applies dynamic range compression. It can accept an input signal and evaluate its volume. If those peak values exceed a threshold, it can attenuate (lower).
This means that if the limiter’s threshold is set to -5dB, then it will prevent audio from being louder than -5dB. Although the audio may seem to get louder as it hits the threshold, the limiter will not allow audio to be louder than -5 dB. However, the maximum amplitude cannot climb higher.
When mixing in the box, we usually set the threshold at 0 dBFS (decibels full scale, the digital scale). We set the threshold to +24 dBu for analog metrics (decibels unloaded). These points represent the equivalent maximum permissible amplitude, and anything higher is considered to be ‘peaking’.
Unintentional peaking, also known as audioclipping can cause distortions or loss of broadcasts or recordings and heat damage to speakers. Clipping is explained in more detail below. A limiter applies clipping intentionally but with care.
https://73b42b2da6a577684b7b20496ec127e1.safeframe.googlesyndication.com/safeframe/1-0-38/html/container.html There are many hardware options
These tools come in two types: software and hardware. Hardware units deal with actual electricity. These units are commonly found in rack mount units at radio stations or music studios. VST plugins for audio workstations, which act on digital signals, are the other type.
What is the difference between a limiter and a compressor?
The main tool to apply dynamic range compression is a compressor. The compressor has a threshold level that is set at a specific decibel level. Any audio above that level will be reduced by a ratio that you can control.
If the threshold is set at -10dB and the ratio to be set to 3:1, then only 1 dB pops out from the other side for every 3 dB over -10dB. For example, the amplitude reaching 1 dB is 9 dB more than -10 dB. Due to the 3:1 ratio, the compressor would lower the peak at -1dB to -7dB (9dB went in but only 3dB came out).
This can be confusing. For more information, please refer to What is the Compressor?. A compressor can reduce audio volume by reducing it by some percentage, but still allows some audio volume to exceed the threshold. Limiters prevent audio from exceeding their threshold.
https://73b42b2da6a577684b7b20496ec127e1.safeframe.googlesyndication.com/safeframe/1-0-38/html/container.html A limiter is a compressor with an infinite ratio
The difference between a compressor and a limiter is simple. A compressor’s ratio is increased to infinity, so a limiter is a sub-type. It puts a stop at the threshold, and it does not permit waveform peak values to exceed this value.
You don’t want to be confused if you aren’t sure what to do.
When to use a limiter
This section could have been called “Why do you use a limiter?” There are three main situations:
- Protect our equipment in live environments
- To prevent live recordings from accidental peaking
- Mastering can be enhanced by increasing the volume of audio
Live sound reinforcement systems that use expensive power amplifiers or mixing boards are not ideal. You don’t want an electrical spike damaging your equipment. Worse, some musicians crank up their guitar to maximum volume and cause loudspeaker damage (and even hearing damage) for listeners.
You may record in a music studio and have the perfect take, but parts of it can sound distorted or distorted. You may have to delete a take and start over, but it will not result in the same vocal performance from your musician or singer again. Limiters would have prevented this peaking from happening.
Limiters are used by mastering engineers to raise the volume of an audio track (or song). You can increase the volume of a song by pushing loud parts, such as snare drums, up to a limiter’s threshold and not causing any distortion.
Today, loudness is a normal part of the entertainment industry. (There’s a fight in the music business called the Loudness war, if you want more information) Because dumb major label executives and TV commercial makers thought that destroying your eardrums would attract your attention in a positive manner, everyone now competes to be loudest.
The limiter makes it possible for all of this, good and evil. You should use one of these whenever you need to protect expensive equipment from excessive voltages or high volumes, or preserve quality in recordings or broadcasts from peaking.
How to use a limiter
These will have a handful settings, but you will only use a few.
- Input Gain
- Release Time
- Lookahead Time
- Soft or hard knees
Logic Pro X’s Limiter Plugin
Threshold– You’ll usually set the limiter threshold to 0dBFS (the maximum value of amplitude). Mine don’t offer any way to lower the threshold.
Input Gain The input gain will not be used unless the mastering process is limited. This is basically a volume control that controls the audio’s quality before it passes through hardware or plugins.
Release Tim – This indicates how long the gain decrease continues after the threshold is reached again. Too long will result in a loud pumping sound. But too short can make it jarring. You can’t set an attack setting as you want the audio to react as fast as possible when it jumps above the threshold.
Lookahead time – This digital time allows the plugin to see ahead in time. It allows it to anticipate when it will have to start reacting, and it increases precision. It is usually set at a very low time of between zero and 10 microseconds.
Knee The knee controls how gradual the loss of weight will be. A soft knee is less obvious, more musical, and more gradual. Hard knees can be abrupt and can make you feel jarred. Except for reinforcement systems that emit loud sounds, a soft knee is preferred.
This is all there is to it. If you are not mastering, your goal is to never use this tool. However, it is always a good idea to have one on hand when recording live. As mentioned above, it is a good idea to have one with you during live performances.
If you are really good at mixing, you can use them. However, the general rule of thumb is not to need it. It is important to know your peak volume to allow you to adjust volume to give mastering engineers enough headroom.
SOFT CLIPPING Vs. HARD CLIPPING
I was lying, there is another thing. We want to eliminate unintentional peaking, as we stated. This causes bad distortion and clipping. It can cause damage to your guitar amps and bass amplifiers as well as your speakers drivers. You may also break your speaker cones.
Clipping can be used for purposes, such as distortion pedals and overdriving an amplifier tube. Clipping is used to prevent peaking and its harmful effects.
This can be done with either soft clipping which creates rounded edges and “cuts off the top” of waveforms or hard clipping that creates a shelf, similar to a plateau. This is what happens at the peaks as well as the troughs. A visual example of hard clipping
Soft clipping, which is relative new, is a preferred method for reducing the abruptness and making it more noticeable to the listener.
Audio Limiters Demystified!
She was done! These tools can be used as a last-ditch defense mechanism in signal processing to help us save time and money. You can place them in different segments of your signal chain, depending on the purpose. They are usually placed right before or after your converters.
You now know the answer to the question “What is a limiter?” You can see that they are useful tools for sneaking out more volume. They also save us from costly loudspeaker equipment or amplifiers. It’s up to you to integrate them into your workflow.