Equalisation (EQ) is the process of changing the balance of different frequency components in your audio signal. A good mix consists of each element within its own sonic space, correct use of EQ enables separation of each track so that frequencies aren’t overlapping and therefore masking/potentially cancelling each other out.
There is no set method for getting vocals right, it not only depends on how the raw vocal recording sounds initially, but also the sonic aesthetic (overall sound) you are aiming to achieve.
… so unfortunately we can’t supply you with a checklist of steps, however, hopefully this article will help you in making more educated decisions and will help you get the top-notch sounding vocals that you’re aiming for!
An EQ allows you to boost or cut incredibly precise frequencies within your audio track, this is performed using an EQ curve, either a bell, shelf, or notch shape. It is one of (if not the) most important stages within the vocal mixing process, however, even a slight over-use of EQ can make a vocal sound thin and unnatural. Remember, less is more. Try not to get carried away with subtractive EQ because you’ll cause more damage than good.
There’s a couple of rules of thumb when it comes to EQing vocals, firstly, cut before you boost... This applies to EQ’ing in general. If your vocal track is sounding full and you are wanting more clarity, cut. Whereas if you want to make the track actually sound creatively different, then boost. As well as this, if you are cutting, (or in other words, applying subtractive EQ) do it before compression, and try to do any boosts afterwards.
In order to understand how to use an EQ properly, you must get to grips with the frequency spectrum. The spectrum is split into bands; lows, mids and highs.
So, with this in mind, here’s a break-down of each frequency band:
Sub-Bass Frequencies (20 - 60Hz)
A human can hear nothing below 20Hz, anything lower than this can only be felt, these kinds of low-sub frequencies are often used within scary movie soundtracks as the sub frequencies provoke a sense of fear and unease. However, when it comes to mixing vocals, there is no need for this subby rumble to remain within the mix. The frequency of most human voices are centered between 120-250Hz, therefore, generally cutting anything below 40Hz will help to avoid ‘muddiness’ in the bottom end.
Bass Frequencies (60-250Hz)
Try setting your High Pass Filter (HPF) to 40Hz and gradually move it up along the frequency spectrum, listening carefully to how the EQ is affecting the sound. When you start to notice your vocal sounding thinner, pull the HPF back a little until you can hear the body and warmth again, typically the point of this HPF shouldn’t be any higher than 120Hz maximum to avoid the chance of cutting out wanted frequencies.
TIP: Use a HPF and LPF to roll off any unnecessary frequencies on all of your other tracks within your mix to free up space avoiding masking, this technique is called ‘bracketing’.
Lower Mid-range (200Hz - 500Hz)
Containing too many low mid-range frequencies is one of the prime ways that a mix can sound muddy and lack clarity. However, similar to the bass band, this zone is typically where you’ll find the warmth and thickness of your sound, so again, beware of cutting too much out here. If your vocals are sounding thin and brittle, apply a small boost of around +3dB with a low Q (low Q values affect a wider range of frequencies that high Q values- visually the EQ curve is wider and less pointed). However, if you are lacking clarity in the vocal, try making a measured cut around 200Hz, this is often the home to the ‘boxy’ sounding frequencies- listen very carefully here.
Mid-range (500Hz - 2kHz)
This is one of the easiest frequency bands to identify, especially around the centre of this area. If you have this ‘honk’ to your vocal sound (try holding your nose and speaking- that kind of sound), a small cut in this section of the mids, around 1kHz should sort this out. Additionally, if you’re facing a problem of intelligibility where your words seem a bit muffled, a small boost can help.
Upper Mid-range (2kHz - 6kHz)
The Upper Mid-range is the area where the troublesome frequencies tend to be apparent. However, it is important to strike a balance, as too few frequencies in this area will result in your vocal having far less clarity. If this is the case, try giving a broad boost to start with and boost more if you think your vocal needs it.
If your vocal track contains sibilance (consonants that produce hissing sounds such as ‘s’ and ‘t’) they will usually appear between 5kHz-7kHz. A de-esser (a type of multiband compressor) can be used to fix this problem whilst not affecting any other frequencies. Sometimes the pesky frequencies are just too prominent and therefore will need an incredibly narrow, surgical EQ cut to remove them.
High Frequencies Band (6kHz - 20kHz)
The high-end frequencies region, is where you can add the finishing polish to your sound. Where a boost in the bass/low-mids can add a weight to your vocals, a little boost in the top end can give your vocals ‘sparkle’ and a sense of ‘airiness’. You’ll want to use what is called a ‘high-shelf’ to do this. It’s called ‘shelf’ after the shape of the boost, which is long and flat. By adding a few decibels to these top-end frequencies with a shelf, your vocals will have a brightness that sounds natural and fresh.
Once you have experimented with EQ for a while, you will realise the importance and power of this tool. Know what it is you are trying to do before you begin- whether you’re using it to ‘fix’ pokey, duff frequencies within a vocal track, or ‘creatively’ alter the audio. Remember to USE YOUR EARS, most EQ’s have an in-built visualizer, but at the end of the day it’s all about what the track sounds like, nobody else can see it! Lastly, beware not to cut too many of the important frequencies out (unless this is on purpose of course), but mostly, have fun! It’s a super tool, and when used right, it really does transform a mix.