This is THE area that most people have trouble with when it comes to using EQ.
For some strange reason, even engineers have to ponder a solution to an EQ problem where the voice is concerned. I always have to think through the whole process taking into account the desired result, the choice of EQ to use, the corrective and creative approaches, and all this married with what my client requires for the market that the mix is aimed at. Maybe not that strange when you take into account the vast frequency range of the voice, coupled with the varying fluctuations (gains) of frequencies over a given length of time.
Add to that the usual problems encountered in recording the voice, like plosives and pops, and you can see that half the time engineers are applying Corrective EQ, as opposed to Creative EQ.
And if that wasn’t enough, singers then go and change the gains across their vocals and fluctuate the frequencies even further by applying vibrato to their voice whilst singing, and it is now even clearer as to why this area of EQ treatment is regarded as the ‘Holy Grail’.
Without a doubt the hardest of all sounds to EQ is the voice.
Whereas drum sounds are one shot and static, in terms of their frequency ranges, the voice encompasses a whole plethora (love that word) of frequencies and at varying amplitudes over a given period. And it does not end there, oh no. You need to take into account the frequency ranges of the instruments incorporated within a mix, and compensate for that as well as trying to line up the voice in the mix.
If all the elements of a mix were static in their frequency ranges, then it would be easy. But since music is not like that, then we have the problem of finding a happy location for each and every instrument and the voice. Now, if the voice has a habit of varying it’s frequencies, then it will ‘invade’ the spaces allocated to instruments.
We will be left with frequency overlaps, clashes, phase, etc. So, the task of ‘fitting’ the vocal into a mix becomes more complex.
Now, let’s take that a stage further and introduce what really takes place in the real world, multiple voices.
A song will invariably have more than one vocal, irrespective of there being only one vocalist. Choruses will entail more than one vocalist, or more than one vocal line. In other words, apart from having another vocalist singing on the song, you will have a number of vocal lines from one singer, or more, that will go to form the chorus or any other part of the song. And it doesn’t end there: most vocals nowadays are double tracked, doubled up for thickness, layered to create harmonies and so on. Add to that the changes in the tonal character of the way the song is sung, and you are faced with even more variables to take into account.
Ok, so the above sounds as if you are going to go through a living hell when trying to EQ vocals but fear not, it is not that bleak.
As we have covered earlier, there are ways to analyse the frequency range (spectrum) of any sound, be it an instrument or a voice. The methodology is the same.
The Spectrum Analyser is a useful tool, so use it. But remember, your ears are the best tools available.
The trick in applying EQ to vocals is to assess what the rest of the audio is doing around the vocals.
Your primary concern with any song, and mix, is to place the processing focus on the vocals because without the vocals you do not have a song.
I often enrich the frequencies around the vocals and then place the vocals in a central frequency band, smack bang in the middle of the mix with careful consideration for additional vocal lines be it backing vocals, secondary vocal hooks etc. Additionally, and crucially, I have to consider the vocals’ frequency ranges so as to accommodate them with treatment to the surrounding frequencies.
This works great for some Dance based music, but not for R&B. In Dance music, I like the vocals to stay rigid in it’s frequency ‘home’, and let the music bounce around it with vocal harmonies accenting the overall feel of the song as opposed to dominating it like in R&B.
With R&B, I do the exact opposite, as the vocals are far more dynamic and flowing, so require a far broader frequency range to move in. In fact most R&B and current Hip Hop songs carry an abundance of vocal frequencies with multi layering harmonies, panned double tracking and so on. On top of all this we have some very dynamically sung vocals that also enter the ‘instrument’ area whereby the voice is used as an additional instrument: high-end falsettos that merge with high-end instrument sounds comes to mind.
We also need to consider separation and layering with vocal lines when we talk about EQ. Considering not only the overall frequency ranges of all the vocals but that of all sounds within a mix will go a long way in resolving any frequency anomalies like masking, clashing etc. Separation is a crucial element of a mix particularly with today’s plethora of multi sound mixes. Cluttered mixes often fail at the first hurdle as they do not offer enough space and depth for the listener to evaluate the sonic content in a pleasing way. Instead they confuse the ear/brain and end up simply being irritating. The same applies to sparse mixes albeit in a different context. A sparse mix will require a great deal of depth and width with sensible frequency crossover points whereby huge gaps of empty space are not left in between the sounds. Sometimes filling out a sparse mix can be even harder than treating a cluttered mix.
Separation is also crucial when it comes to vocals as the small nuances of the vocal delivery require that the whole transient nature of the sound be heard. Words, letters, sustained notes etc must all be distinct and heard with clarity and depth. The same can be said for all the musical components within a mix.
As we discussed earlier, EQ is a great tool to use if you need to separate instruments and vocals in a mix, but we didn’t really touch on using EQ when we layer sounds, specifically vocals.
Before we get our teeth into some vocal EQ examples, I would like to briefly touch on the subject of Primary and Secondary EQ.
Exctract taken from EQ Uncovered.