What Does A Limiter Do In Audio & How To Use It
Oct 20, 2024
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Tero Potila
So you have spent hours carefully pulling your faders back to keep your mix clean, but you're left wondering how to achieve that competitive, industry-standard loudness without crushing the life out of the dynamics. To bridge that gap, you need a limiter.
Think of an audio limiter as a security guard standing at the exit door of your audio signal path. Its only job is to make sure no audio peak exceeds a set maximum level.
By acting as an absolute wall, the limiter protects your mix from clipping while allowing you to boost the overall volume of your track to commercial standards.
In my opinion, learning how to properly use a limiter is one of the most important steps in modern music production, helping take your mixes to the next level.
It can mean the difference between a track that sounds polished and competitive and one that sounds crushed and lifeless.
Let’s break down everything you need to know about what a limiter does and how to use it effectively in your mixes.
What Does a Limiter Do in Audio?
To understand a limiter, it helps to look at its close relative: the compressor. Both tools reduce the dynamic range of an audio signal, but they do it with different levels of intensity.
A standard compressor gently squeezes your audio with a lower ratio setting, such as 2:1 or 4:1, allowing some of the loud peaks to pass through.
A limiter is like a type of compressor on steroids. It uses an extremely high ratio, typically starting at 10:1 and going up to 100:1 or even infinite:1.
This means that once a signal hits the set threshold, it is stopped dead in its tracks. No matter how hard you push the input signal, the output will not cross the line.
Placing the limiter at the absolute end of your signal chain is the golden rule of mixing and mastering. This ensures that all your prior adjustments, such as EQ boosts, audio compression, and spatial effects, are taken into account before the overall level is set.
Limiter vs. Clipper: What Are the Main Differences?
It’s easy to confuse a limiter with a clipper plugin, but they handle occasional peaks in very different ways.
A clipper acts like a pair of scissors, abruptly chopping off any peaks that cross its threshold. While this can add a pleasing grit and warm harmonic saturation to genres like rock or lo-fi, it can easily sound harsh if overdone.
A limiter uses a broader, more flexible form of gain reduction. Instead of chopping the top off the waveform, it quickly turns the volume down and then back up.
This gives you a much cleaner, more transparent sound, making it the perfect choice when you want to protect your dynamics without introducing unwanted distortion.
Essential Limiter Controls
To get the most out of your limiter, you need to understand its primary parameters.
Here are all the common controls you’ll find on most limiters:
| Parameter | Function | Practical Tip |
|---|---|---|
| Threshold | Sets the level where limiting begins. | Lowering this increases average loudness. |
| Output Ceiling | Sets the absolute maximum peak level. | Set to -0.3 to -1.0 dBFS to prevent clipping. |
| Attack Time | Determines how fast the limiter reacts. | Keep this near-instantaneous for brickwall protection. |
| Release Time | Determines how fast the limiter lets go. | Adjust until the gain reduction meter moves smoothly. |
| Lookahead | Allows the limiter to see peaks before they hit. | Always enable this on masters for zero-overshoot security. |
Some modern limiters also include a knee control, which determines how smoothly the processor transitions into applying gain reduction.
While a hard knee clamps down aggressively the microsecond your audio hits the threshold, a soft knee starts applying gentle, gradual compression just before the peak crosses.
My advice on using the soft knee setting: Dialing in a soft knee can keep transitions sounding natural on a vocal or instrument bus, but keep in mind that it technically defeats the “brickwall” safety of a mastering limiter.
Because a soft knee begins compressing early, it can allow rapid peaks to overshoot the absolute threshold, causing digital clipping.
For mastering, stick to a hard knee.
Brickwall vs. True Peak Limiting
When it comes to mastering, you’ve probably run into the terms brickwall limiting and true-peak limiting.
A brick wall limiter is exactly what it sounds like: a hard stop that prevents any digital sample from exceeding your output ceiling. It is the ultimate safety net for your master bus, ensuring that your track never clips in the digital domain.
There’s one catch: standard brickwall limiters can miss something called inter-sample peaks.
When a digital audio file is converted back to analog sound by speakers, the gaps between digital samples can sometimes cause spikes and distortion.
This is where true peak limiting comes in. True peak limiters oversample the audio internally to detect these hidden peaks and apply gain reduction before they can cause distortion.
While online distributors won’t reject your files for going over, major streaming platforms like Spotify and Apple Music strongly recommend keeping your True Peak ceiling at -1.0 dBTP (or -2.0 dBTP for louder, heavily compressed tracks).
This safety margin prevents the lossy encoding process (converting WAV to MP3 or AAC) from introducing unwanted distortion.
How to Use Limiters in Your Mix
While limiters are most famous for their role in the mastering process, they are a powerful tool throughout your mixing process as well.
The key is knowing when to use them and how much limiting to apply.
Limiting Individual Tracks
You definitely don’t need to limit every track, but a limiter is a fantastic tool for taming highly unpredictable elements.
Vocals, for example, can have sudden volume spikes that a regular compressor struggles to handle smoothly.
It’s a good idea to place a limiter at the very end of your vocal chain, set to only catch the absolute loudest moments. It can help keep the vocals perfectly balanced in the mix.
In my experience, it’s best to aim for a conservative -1 dB to -2 dB of gain reduction on individual tracks.
This tames the peaks without making the instrument sound flat or lifeless.
Limiting Mix Buses and Drums
The drum bus is another prime candidate for limiting. Drums are full of fast, fast transients from the snare and kick.
A subtle limiter on the drum bus can glue the kit together and manage those high peaks collectively.
I have to warn you, though; Be careful when limiting low-frequency heavy tracks like a kick drum or bass track.
Because low frequencies have wider waveforms, fast limiting can easily distort the bass and rob your mix of its punch.
If you want to tame a kick drum, try a transient shaper or a soft clipper instead.
The Master Bus
If you have the budget to work with a mastering engineer, that’s, of course, the best option, as they have the latest audio equipment and specialize in dialing in the mastered sound.
But if you’re interested in mastering yourself, read on!
The master bus is where the limiter truly shines. Positioned at the absolute end of your mastering chain, the limiter is your final line of defense.
You can use it to bring your overall mix up to competitive, commercial volume levels while protecting it from clipping.
Here are my recommended steps for doing this:
- Set your output ceiling between -0.3 dBTP and -1.0 dBTP (or dBFS if you aren’t using a True Peak limiter).
- Gradually lower the limiter’s threshold (or increase the input gain) until you reach your target loudness. Aim for roughly -14 to -9 LUFS depending on your genre.
- Keep a close eye on your gain reduction meter; for a clean, natural sound, aim for no more than 2-3 dB of gain reduction on the loudest parts of your song.
- Fine-tune the release time until the gain reduction meter bounces back to zero in rhythm with your music to avoid audible pumping or distortion, and engage oversampling if your plugin supports it to keep the high-end clean.
How to Use a Limiter in Soundtrap
If you’re working in Soundtrap Studio, here is how to load and use Soundtrap’s dedicated Limiter on your tracks:
- Select your track and click on the FX button on the right side of the screen to open the effects panel.
- Click on Add Effect, search for Limiter, and select it from the menu.
- Adjust the Threshold level to set where the limiter begins to engage.
Lowering the threshold pushes more of your signal into the limiter, which tames those sudden volume spikes and increases the overall perceived loudness of a track. - Set your Release time to determine how quickly the limiter stops compressing after a peak passes.
A faster release keeps things lively and punchy, while a slower release is perfect for smooth, transparent control over vocals or acoustic instruments. - Listen closely to make sure you are not over-limiting.
The goal should be to set the threshold so that it only catches the absolute loudest transients, leaving the natural dynamics of your track intact.
With this dedicated Limiter in your toolkit, you can easily tame wild vocal spikes, tighten up your drum bus, and keep your overall mix beautifully clean and controlled.
You can also master your entire song inside Soundtrap, taking advantage of the built-in mastering presets, like Classic or Punchy.
These presets work 100 percent in the background, automatically handling all the complex EQ, compression, and limiting decisions on your master file to deliver a professional, distribution-ready track.
Conclusion
At the end of the day, a limiter is one of the most powerful tools in your production arsenal.
It’s great for anything from catching rogue vocal peaks to gluing your drum bus together or pushing your final master to commercial loudness.
The goal is always the same: to protect your sound quality and let your music shine.
The most important tip I can give you is this: Remember to trust your ears over your meters.
If your limiter is making the track or entire mix sound flat, crushed, or distorted, slowly pull the settings back until you hear the music breathe.
About the author
Tero Potila is a professional music composer and producer. His career combining knowledge and experience from music, TV, film, ad, and game industries gives him a unique perspective that he shares through posts on teropotila.com.
