While conventional EQ may solve one problem, in an ever-changing mix sometimes it can create unwanted holes or bumps elsewhere. We show you how dynamic EQ lets you keep what you want and lose what you don’t.
Static EQ, Dynamic Mix
Traditional equalisers are right up there with the channel fader as an essential mix-defining tool, and any mix not featuring some kind of parametric EQ is certainly unusual. It’s true to say that most engineers will always get the sound right at source wherever possible; the question is what is ‘right’ once a layered production starts to come together? It’s only when everything is in place that the tonal suitability of a sound comes into focus. Experience will lead many to get a head start by knowing what will work before they even press play. Avoiding overlaps is harder to anticipate though, and the odd surprise is often waiting, especially anywhere along the wide vista of midrange.
Achieving the correct levels and maintaining an even spectral balance are arguably the most important things to get right in a mix, indeed they could be the only things that really matter to many mixers. The time honoured technique of applying EQ cut in any given band to let through another ‘competing’ mix element is the tried and trusted approach. This could be the classic low mid cut to a kick for the basses’ clarity, or a scoop in the middle of harmonically-rich guitars to let the vocal punch through. It works, but it has its caveats.
Whenever a subtractive EQ is made at a ‘problem’ frequency to deal with a cyclic momentary clash, such as on said kick or guitar, that same instrument loses information in that band even when the clash isn’t occurring. What we need then, is an EQ that only applies cut (or boost) when required.
Dynamic EQ, Stable Mix
Any mix is “dynamic”, in that it changes over time. In the context of a music mix, events where spectral compensation needs to happen often follow a pattern that is related to the music itself. Dynamic EQ is a development of the traditional go-to parametric EQ that adds variable gain to a band (or bands), allowing equalisation to be level-dependent. Although similar to multiband compression, the two are not the same thing which you can read about here. The big advantage of using a dynamic process to control spectral content is that useful information doesn’t get discarded when the need to cut disappears. This makes it incredibly useful when using cut to make room, as the element to be cut retains its entire tonal personality in-between problem events. Conversely, boosts can be made to make sounds ‘pop’, without exacerbating noise or artefacts. An example of this would be applying boost to the top of an acoustic instrument for brilliance except at finger squeak events.
In this video, we use FabFilter’s Pro-Q 3 to redress the musical balance of a keyboard part. Harshness in the mids obscures the entire part, but a static cut would rob the whole song of useful information in the same frequency band. Applying cut at the problem frequency only when needed keeps information there when the instrument is playing a different chord or in a different key.
Dynamic EQ Is Your Friend
Changing the spectral balance of sources over time allows the engineer to interweave sounds in a way that static EQ cannot. Without it, they must resort to destructive broad-brush moves, or even fader automation running the risk of losing energy where it’s needed. Being able to make more balanced, fuller mixes makes dynamic EQ something to make friends with.