If you have read articles about mastering, you probably understood that you need to use equalizers, compressors, and limiters.
But in what order should the plugins be placed?
Should the compressor come first? Or the limiter?
Simply put, what is the ideal effects chain in mastering?
Well, I propose to explore this topic in detail through this article, illustrated with some audio examples that I invite you to listen to on good headphones or speakers to more easily perceive the subtleties (because mastering, believe it or not, can be very subtle).
What is a Mastering Chain?
Let’s start by agreeing on the definition of what a mastering chain is.
Mastering is the step that directly follows the mixing phase.
It is often compared to the varnish applied to a finalized painting: it’s the last moment when you can correct anything in the sound, but also the moment when you enhance the mix to make it sound even better and/or louder.
Even more
As such, it is impossible to define a standard processing chain that would always be adequate.
However, there are still certain generalities, some common approaches that can be somewhat theorized.
This is what we will see in the continuation of the article. 🙂
The classic plugin chain for mastering
A fairly classic approach is represented in the following diagram:
First, we address the frequency balance, then we control the dynamics of the signal, then we correct the stereo image if necessary, and finally we raise the level with a limiter.
But again, this is a theoretical approach, and in practice, there are often more plugins used: for example, we might sometimes tend to equalize before and after adjusting the dynamics…
However, I propose to delve a little into the details of this mastering processing chain by relying on a passage from the track “The River” by Chris Finegan, from his album Pillars.
Here is the raw audio file:
Step #1: Frequency balance correction
The very first thing I tend to do when mastering a track is to add an equalizer.
There are indeed almost always things to clean up in the mix, for example, an excess of energy in the bass, highs that are too recessed, or a voice that could gain in intelligibility.
Of course, there are all sorts of equalization techniques in mastering to correct all kinds of problems.
But what is important is to only correct what you hear: do not equalize frequencies where you do not hear a problem out of habit or because you read it on the Internet.
An interesting but somewhat advanced approach is to use a mid/side equalizer, as I did on Chris Finegan’s track, to treat the center signal of the stereo image and the signal positioned on the sides separately.
Thus, in our example, I notably:
- opened the highs a bit more on the sides than on the mids, since the mix was too dark
- cut the lows in the side to gain precision;
- corrected a small residual resonance in the mix around 450 Hz;
- slightly lifted around 1700 Hz to make the voice stand out more clearly.
(you can see everything in the screenshot of FabFilter Pro-Q 3 a bit higher up).
Here is the result:
Already, we have something more pleasant, but it’s not over.
Step #2: Dynamics correction
Often, the second phase of mastering will consist of adding a compressor to make the master denser, to give it more cohesion, adding what is called “sound glue”.
This is part of what helps give a “professional” sound to a master, even if sometimes it may seem subtle at first glance if you don’t know what to listen for.
You can also use a compressor to control the peaks of the signal, for example, if you have percussion that stands out a bit too much: this will help bring the instruments into the mix, but it will also simplify the work of the limiter that will come a bit later.
On our example track, I slightly compressed the signal to bring the voice closer to the guitar, while also coloring the sound a bit since I selected the Novatron plugin from Kush Audio, which adds harmonics generously through saturation circuit simulations:
Step 3: Stereo Image Control
Once you have managed the dynamics and frequency balance, it is often useful to add a plugin that allows you to adjust the stereo image of your master.
For example, a stereo imager like the one included in iZotope Ozone (see image above), or why not a mid/side equalizer.
With this type of tool, you will be able to make your master wider if necessary, or conversely make it a bit more mono if it has been mixed a bit too extremely.
However, this is not an essential processing step: often, the width of the stereo image at the end of the mix can be correct and not require adjustments.
Here in our example track, I find the guitar too central, which necessarily gives a somewhat mono sound since the voice is centered in the mix and there are no other instruments.
So, I used Ozone 10 to gradually widen the high-frequency bands, which gives a more natural effect (which will be heard more on speakers rather than on headphones):
Step 4: Final Loudness Management
The last step of mastering, in this case, never changes: we add a limiter (or maximizer, it’s the same thing) plugin to raise the overall loudness of the track.
And now, it’s up to you to judge:
- either you want something that sounds very loud, but in that case, you will limit (= compress) the signal a lot and have distortion;
- or you want something that breathes, and in that case, you will just raise the level a bit and the limiter will only react subtly to control a few peaks here and there.
In our example, I made a somewhat intermediate choice: the limiter kicks in quite noticeably on the parts where the voice is strong, but does not compress the signal on the quieter parts.
This brings us to a more finalized rendering (watch your ears, the example is therefore louder than the previous ones):
And there you go, we have mastered our track!
The Last Link in the Processing Chain
In a mastering chain, there is one last plugin that I recommend you add at the beginning of the processing: a metering tool, that is to say, a measurement tool.
In other words, a plugin that will allow you to track different loudness indicators, such as Loudness in LUFS, which can be relevant to keep a critical eye on what you are doing and ensure, for example, that you are not over-compressing or over-limiting your master.
In fact, this type of plugin has no sonic effect on the sound: it just provides you with objective information that can be useful during mastering.
And Now?
There you go, you now know what a “standard mastering processing chain” looks like.
Now it’s your turn :)!
That said, if you are a beginner, I can only advise you to take a simple approach to mastering. Just with only 3 or 4 plugins, in line with the chain proposed in this article: the more effects you add, the more likely you are to make mistakes.
So keep things simple, and you will see that your results will be better.
To go further, however, if for example you want to learn in detail basic or advanced mastering techniques, know that I will soon release a complete training dedicated to mastering in a home studio context. Follow this link to leave your email and be informed when it comes out 😉