Advanced Vocal Mixing Equalization

Advanced Vocal Mixing Equalization

When mixing your vocal, you can use equalization in advanced ways – like using a side-chain dynamic EQ technique to separate your vocal and another instrument.  Or you can use modulation and saturation to alter the frequency response in either a dynamic or time-based way.

Side-chained Dynamic EQ

I’m not sure how many equalizers can do this, but if you know of some other than the pro-Q 3 let me know in the comments!

Anyway, what I’m going to do is insert the mixbus as my external side-chain.  You could export the instrumental or route the instruments to one bus and use this as the external side chain – whatever works best for you.

Then, I create a band and make it dynamic.  You’ll notice that it’s responding to the signal on which the EQ is inserted.

But, if I click where it says Auto, you’ll notice a very small side-chain icon.  When I click on it the external sidechain, in this case, the instrumental mix is triggering the dynamic equalization.

This way whenever a particular aspect of the instrumental is loud, I can expand the range of the vocal.  For example, let’s create a band at 2kHz and use a positive range.

Now whenever the instrumental’s 2kHz would’ve masked the vocals, the band expands, making the vocal cut through.

Dynamic Inverse EQ

Inverse EQ is a hard trick to beat, but if you make it dynamic it’s even more impressive.  Like before, we’ll use the instrumental mix as our external side chain.  Then we’ll enable EQ match, and set the Reference to External Side Chain.

We’ll then match the vocal’s response to that of the instrumental and delete some of the more extreme bands.  This includes ones with a high amplitude in either direction or super high or low frequencies.

Then let’s highlight all bands, and subtly invert their gain.  This way what made them identical now separates the 2, causing more distinction.

If you’ve heard of this technique before, sorry for being redundant – but there is one more aspect that we can add to it.

We might not be able to do this for all bands, but for the most important ones, right-click and make them dynamic.  If you do this, make the band closer to unity or the centerline, and allow the dynamic band to do the majority of the work.

Best to use a low-latency linear phase setting when doing this.

LFO and Saturation

Using the FabFilter Saturn 2 we can create modulation that affects the frequency response of our vocal.  Granted this isn’t equalization in the traditional sense, but it’s a cool effect nonetheless.

I’ll explain how to set it up first, then go into why it works and what’s happening.

What I’ll do is create 3 bands for the lows, mids, and highs – then I’ll add some harmonic distortion to the mid-channel and slightly lower the amplitude of the lows and highs.

Next, I’m going to create an LFO in the modulation section and link it to the crossovers.  What this does is modulate the point of crossover, in turn changing the frequency of the band.

When soloing the mid-band we can really hear the effect, but since the other frequencies are present normally, what this is really modulating is the frequency of the distortion.

To improve this effect or make it a little more musical, I’ll create an enveloper follower, switch it to transient mode, and then link that to the crossovers as well.  Then I’ll blend the effect on the crossovers between the LFO and envelope follower. 

Emulate Microphone Capsules

This effect is easy to accomplish; however, it’s advanced because it isn’t thought-about too often or discussed.

In short, if we want to emulate a particular microphone, we can look up the response of the capsule or the mic itself, and then impart a curve onto our recording via our EQ.

For example, the original Neumann U87 has a subtle low-cut from 20Hz to 70Hz, that goes about as low as -8dB.  Then it’s primarily flat until we get to 7kHz. 

There’s a slight bell at 10kHz of about 0.5dB, and then a slope afterward which attenuates the high end – we can use a very subtle low-pass filter to accomplish this.

Now, we just need to emulate minute curves to give it a unique sound.

One thing to keep in mind is the curve of the microphone you used – you’ll need to perform a conversion if your microphone and pre aren’t relatively flat.  Fortunately, most interface pres are pretty flat – as are many modern microphones.

Emulate Microphone Preamps

Similar to microphone capsules, microphone preamps have particular curves that you can emulate.

This info is a lot harder to find and takes combing through various thesis and scientific papers, but here are some of the frequency curves for popular mic preamps.

The Neve 1073 has a slight low dip below 20Hz, and some very gently attenuated lows to low mids.  It’s flat from a little above 500Hz to 2kHz. 

It then dips by about -0.3dB and goes back to unity above 20kHz.

The API 512c on the other hand looks much different.  In the lows, it has a 0.2dB infrasonic boost that slopes down to unity by about 40Hz.

There’s a slight, less than 0.1dB dip between 50Hz to 400Hz, that tilts upward, crosses unity at about 700Hz, and then acts almost like an air shelf where the amplitude extents to about 1dB above 20kHz, but still affects perceivable frequencies to an increasing extent above 2kHz.

We’ll include these curves as presets in future preset packs.

Some great advanced vocal mixing equalization techniques include side-chained dynamic equalization, dynamic inverse equalization, LFO modulated saturation, as well as both microphone and preamp emulation with an equalizer.  These effects typically work well independently but can be combined when equalizing your vocal in an advanced way.

Get a FREE Mastered Sample of Your Song ➜

Sage Audio Mastering

Nashville, TN