Music Industry

How To Use Limiters / Limiting Explained

limiters-limiting-explained

Everybody seems to want to use Limiters, but only a handful of people go about it the right way. If you don’t know what you’re doing, using a limiter will do a lot more harm than good. Want to know what limiting is, in which it differs from compression and how you should use it? Want to know what Gandalf the Grey and Limiters have in common? Find out in How To Use Limiters – Limiting Explained.


What Is Limiting And What Does It Do?

The word itself is a dead giveaway. With limiting, you’re – there it is – limiting the dynamic range of an audio signal. With dynamic range, we mean the difference in volume within a mix over a certain amount of time. Traditionally speaking, a limiter is used as a safeguard against clipping, simply because it cuts everything below the set threshold. The below chart – courtesy of Practical Music Production – explains it quite well.

As you can see, it’s quite simple. If a threshold of 20 dB is set for the limiter, not even the tiniest of peaks will go past that level. This makes it the perfect tool to use when you don’t want your volume levels to go into the “red”.

What Is The Difference Between Limiting And Compression

The above chart also shows us the difference between Limiting and Compression. The simplest answer to that question would be saying that they’re essentially the same, but there is one difference. And that difference lies in the ratio.

Both Limiters and Compressors are tools that reduce the dynamic range of an audio signal. Given the right setting, a compressor could even act as a limiter. Since limiting is meant to act as a shield against all peaks, it makes use of an infinite ratio. As explained in our article about Compression, the ratio setting determines how ‘hard’ you’re squashing the parts of a sound that exceed threshold level. A ratio of 8:1 would mean that a signal of 8 dB over threshold level would be compressed until there’s only 1 dB left that exceeds that level. Alternatively, a ratio of 20:1 would mean that a signal of 20 dB over threshold would be reduced to 1 dB over threshold, which boils down to a whopping 19 dB of gain reduction. Note that compressing audio with a ratio of 10:1 or higher is generally considered limiting.

In the case of a Limiter’s infinite ratio, this would mean that the sound will be compressed so hard that not even a single peak is allowed to go past the set threshold, no matter how small or short those peaks may be. There’s no room for mercy. Think of Gandalf fending of the Balrog in Lord Of The Rings. “You Shall Not Pass”. Till here and no further.

When Do You Use Limiting?

When it comes to Limiters, most (up-and-coming) producers have only one reason for using one. They’ll tell you they want to use limiting – or have already done so – to make their mix louder. Now, with the loudness war in full effect and all, we get why. And it’s not even wrong to think so. But the danger lies in pushing your limiter too far.

Limiters In Mixing

Many people seem to believe that Limiters can only be used as a mastering tool, but this isn’t true. As a creative tool, a limiter can boost the perceived volume of a certain sound. It can also be used to restrain unpredictable effects or automated sounds that have too much dynamic range. You’d simply be using the Limiter as a heavy-duty Compressor (a Compressor with a very high ratio). If pushed ever harder, it can even bring (groups of) sounds to the forefront of your mix, as long as you’re not using it on too many other sounds as well.

Limiters In Mastering

In mastering, the use of a Limiter is a little more straightforward. It’s all about increasing the perceived volume of the entire record. When your mix is good and balanced, the only things that need cutting are the transients of sounds: small sound bites that aren’t even a fraction of a second long. If you set the threshold just right, the limiter will cut those peaks without any audible side effects, which is called Transparent Limiting. Of course, you’re free to push the limiter just a little further if that extra bit of pump is what you’re going for. Just know that if you push the limiter too far, you’ll end up with an inaudible mash of noise.

 

So Why Does Compressing Or Limiting Make A Sound Seem Louder?

As you know, compressing – or limiting – turns down the loudest parts of an audio signal. This effectively leads to a smaller dynamic range, the difference in volume within the audio signal. So let’s say the dynamic range of your sound is 5 dB – 20 dB and the applied compression results in 2 dB gain reduction. You’ll end up with a dynamic range of 5 dB – 18 dB after compression.

But… that’s not louder. You’re right, it isn’t. The peak volume started out at 20 dB and has now been decreased to 18 dB. So, how do we go from an audio signal that’s even lower in volume to one that seems louder than before? This is where the Make-up Gain (or Output Level) setting comes in.

With the Make-up Gain setting, you can make up for the loss of volume after compression. It simply adds volume to the entire sound. This is important to remember. It doesn’t just boost the peak volume, it boosts everything. So after compression took 2 dB off of the peak volume (20-2=18), you can now add 2 dB via the Make-up Gain setting to bring the peak volume back to its original level (18+2=20). But here’s what’s different.

While compression or limiting left the quietest parts of the audio signal untouched, the Make-up Gain did not. This means that the bottom end of the dynamic range – 5 dB in our example – remained at 5 dB after compression, but then got 2 dB boost from the Make-up Gain (5+2=7). Where the dynamic range was 5 dB – 20 dB before, it is now smaller: 7 dB – 20 dB.

Essentially, this means that while peak volume has remained the same, the quietest parts have become louder. So even though the sound itself hasn’t technically increased in volume, the average volume did. And our ears perceive this as the sound being louder.


Are you having trouble with certain aspects of music production. Want us to explain? Hit us up in the comment section below. We might just take your problem and turn it into an explanatory article to help you – and others – out.

You Might Also Like

5 Comments

  • Reply
    Daniel
    January 28, 2018 at 11:31 pm

    Thanks for writing all these posts Ruben! Great reading. I like how you explain the concept so easy and understandable.

    • Reply
      Ruben Meijer
      January 29, 2018 at 2:15 pm

      Hi Daniel,

      Thanks, glad to be of service!

  • Reply
    Ivan Milenin
    April 12, 2018 at 10:13 pm

    Hi, Ruben.

    I have some news to tell you. So, I completed 2 songs, and so far, everything is about to be balanced. I now knew how to EQ properly, how to set up the gain staging, keeping my levels from clipping, and set up bus routings. This is because I bought a new computer as you suggested, (an iMac Mid 2011 computer with 16 GB RAM,) and my workflow improved tremendously!!

    Of course, it may have a few system overloads, but honestly, I experienced almost none of those overload messages, and my situations with the CPU are over. Now I was able to complete the song, but I have a concern to tell you.

    My mix is getting there to be crispy and clear and well mixed, but now I experienced a loudness war. (I know that term is used often by most people). As a watched other tutorials, I want the goal to reach -10 dB of RMS level to get the song to be loud. But the question is, do I have to reach -10 or -8 dB range of headroom for my demo to be accepted? My hunch is that it has to do with the limiter. Furthermore, I don’t want to make it too loud or too quiet; I’m not good at mastering, and I don’t want to ruin my mixdown. Any I idea on what to do with the limiter?

    I have every faith of you help me with advice. You are always trustworthy.

    Thanks,

    Ivan Milenin.

    • Reply
      Ruben Meijer
      August 17, 2018 at 11:55 am

      Hi Ivan,

      Sorry for the delayed response. Using limiters is a very tricky business. Sure, it can help you get that pump in your sound or just more loudness overall, but you don’t want to kill the dynamics of your mix (it’s a VERY fine line). The number one rule for me is to lay off the limiters until you know exactly what you’re doing. If you think your mixdown is perfect, but you’re not sure about what to do in terms of mastering (or limiting), it might be wise to contact a professional to see what he can do for your mix (and master). That’s the safe bet. Additionally, the mastered version you’ll receive provides you with an example you can try to recreate yourself, to help you get a better understanding of it all.

      Your other option is to keep practicing with limiters as you compare your versions to other, professionally mastered songs. Work on it till you feel you’ve got it right. It might be a lot of hit and miss, but in the end, this is a great way of learning and progressing. It might take a whole lot longer to achieve the sound you want though. That’s why mastering services exist.

      On an addition note, you’re talking about reaching -10 dB of RMS. Understand that RMS is (in simple terms) the average volume, so it’s not the same as headroom. Headroom is the amount of volume space between the loudest peak in your mix and the nominal volume value of whatever your sound system can handle. So if your peaks go as far as -3 dB and your nominal volume value is 0 dB, you have 3dB of headroom. This space can be used to further process the sound or the mix, such as through mastering. A limiter cuts (or heavily compresses) the peaks of your audio to create some more space/headroom, which allows you to turn the overall volume up a bit more without causing distortion (which happens if you peaks exceed the maximum. This higher overall volume means translates to a higher RMS level. As for demos, I’d stick to your best/most clean mix plus MAYBE a small amount of limiting. It’s better to send a clean mixdown without limiting than to send a demo that’s been limited too much.

      Hope this helps!

  • Reply
    Steve
    April 19, 2018 at 5:31 pm

    I like the way you explain things in these articles, thanks for making them!

  • Leave a Reply