Mixing part 3: EQ
The Equaliser – or EQ – is the Swiss army knife of mix equipment. It’s the tool you will use to carefully sculpt each sound to reveal the beauty within. If sound elements were made of wood, EQ would be the craft knife you use to carefully whittle at the edges so that they all fit nicely together.
I have just the tool for the job, ma’am.
As stated in the first part of this series, all sound has energy, and this energy is spread out over various frequencies. As we begin to add sounds together, we find (particularly if they’re at all similar) that frequencies in one sound begin to drown out other sounds, or combine with other sounds to create booms and ringing tones, so that things get muddied.
In this case, we need to shave off some of the offending frequencies so that everything can shine through as it should. And EQ is the tool we use to do this.
EQ enables you to either boost or cut energy in a sound at specific frequencies, literally allowing you to shape it exactly as you’d like.
Before we can discuss how to use EQ in the context of a mix, we need to talk a bit about how to to operate them. There are two basic types of EQs that you will encounter.
The Graphic Equaliser
Graphic EQs are the kind you’re used to seeing on hifi equipment, but you also find virtual versions as plugins for sequencers. They have a row of sliders that can either boost or cut, at specific fixed frequencies. They’re limited for very fine work, but this limitation also makes them extremely easy to use.
How to use it: Don’t. It’s lame. If you must, then pick the slider that’s closest to your problem area and either cut or boost. But don’t tell your friends, they will laugh at you.
The Parametric Equaliser
Parametric EQs are far more powerful in that you can boost or cut at any frequency you choose. They are the audio equivalent of a surgical scalpel. They’re trickier to use because their flexibility is infinite, but with practice they produce the best results.
How to use it: Use the controls to pinpoint the frequency you want to work on, and either cut or boost. More below.
Less is more
What I’m about to say is subjective, and you may learn other lessons elsewhere. But in my experience, it is far better to sculpt a sound by removing energy from it than by adding energy to it.
This is for two basic reasons, in my opinion. One, because when you mix, you are trying to create space for everything to fit. You don’t create space by adding more stuff in.
And two, because on a practical level, it’s hardly ever possible in practise to boost just a single frequency without adding energy to the surrounding frequencies, often with unintended consequences. You can nearly always achieve the same result by removing energy elsewhere in the frequency spectrum.
This is why I always refer to EQs in analogies of cutting instruments like knives, scalpels, etc.
What does this knob do?
I’m going to focus now on how to use a parametric because really, this is the tool you need to know how to use. Almost no one uses graphic EQs anymore, for a every good reason: THEY’RE OLD AND CLUMSY.
Also, I must preface this by saying that yes, most parametric EQs have more controls than this, but you need to understand the basics of the tool before we can move on to advanced ninja stuff (covered in Part 4).
Nearly all EQs default to what is known as Band Pass mode, so we’re going to investigate that first: 99% of the time, this is what you’ll use.
Most parametric EQs have at least 3 basic controls:
Gain controls how much energy we’re going to add or remove from the sound. Most often you’re looking to just carve a bit, not nuke it from orbit.
This knob controls which frequency we’re going to work on. You can sweep it from the very low bass (40Hz) all the way through to the very crispy top end (around 16kHz and above).
Q (aka Width)
So, we’re going to be carving a chunk out of the sound. The Q controls how big of a chunk.
Think of it as the width of your chisel. A high Q value allows you to cut a very fine slice, right at the frequency you are targeting.
A low Q value allows you to carve a huge fat hole in it, taking out not only the target frequency but doing a fair amount of collateral damage to the neighbouring frequencies as well. It all depends what you’re trying to achieve.
Now that you know what the knobs do, let’s look at how to use them.
Parametrics in the Mix
So, you’re listening to your track, and suddenly this one sound is just really annoying you. It sounded good on its own, but now in the context of the mix, it’s somehow … wrong. Sounds like it’s ringing somewhere.
Parametric EQ to the rescue. Here’s what we do.
First, don’t solo the sound if you can help it. Mixing is about context, and you only started hating the sound once you heard it with the others, so it makes sense to EQ it while hearing the other sounds in the mix too. There may be times when it makes sense to solo, but for the most part, don’t.
Now, insert a parametric EQ into the relevant channel – some sequencers might have a decent EQ built right into the channel, but maybe you prefer a particular plugin. For example, I have an ongoing love affair with Waves REQ.
Once the EQ is online and ready to go, start by pushing the Gain control way up, to create a huge spike. I know, it sounds counter-intuitive, but trust me on this. Depending on the EQ, you may want to narrow the Q a bit, but not too much.
This next bit is where your ears come into play. Grab the Frequency controller, and sweep it backwards and forwards nice and slowly, from one end of the spectrum to the other, and back again.
Take your time. You’re looking for the spot in the sound where it sounds worst. When your spike crosses the point where the ring is occuring, it’ll cause the peak to become even peakier. Trust me, when you hit it You Will Know.
Centre your spike on the offending area, and pull the Gain controller down below zero, cutting energy at the naughty spot.
Sounds much better, doesn’t it?
And you’re done.
In the next part of the series, we’ll look at Filtering – the art of using an EQ to shape sound and perform cool effects.