Equalization (EQ) is one of the fundamental steps in mixing audio. Wether it’s a live performance, a music record, or sound for film, EQ is used to along side volume or gain to create balance in your mix. It helps me to visualize the frequency spectrum of human hearing in my head when I begin to plan a mix. EQ is the main tool that I have to set certain instruments in particular frequency ranges. If we tried to push all the elements or instruments in a mix at all the same frequencies there would be not definition, and all the instruments would sound mushed up together. The first sign of a good mix is always the balance. It doesn’t matter how many cool effects are in a mix, or how much genius automation, if the balance is off it will never reach it’s full potential. So how does one achieve a good balance? Read on my friend.

Like I mentioned earlier I try and visualize the frequency spectrum in my head and then make a plan as far as which instruments I will place where. The first step when applying EQ is filtering. The recording process is not perfect, and I can’t see how it will ever be, plus I’m a subscriber to the theory that when one is tracking one should capture the whole sound (i.e. I don’t EQ signals when actually recording them to tape or disk) Filtering is the process of eliminating all the parts of a signal that you know you don’t want, and or won’t use.

EQ Video

I will typically roll off the bottom end of almost all the tracks (possibly not the Kick drum or Bass guitar… possibly). For instance the electric guitar (especially through and amp) rarely outputs anything useful below 80 Hz. Rumble and other non-audible frequencies like to hang out down there as well so it’s good to deep six those before they start taking up your precious headroom. As a general rule you can pass though each of your tracks with an EQ plug-in or use a desk/console if you have one, and roll off the low frequencies until you can hear it effecting the sound of the instrument and then back it off a little. This will do wonders for your headroom and tighten up your mix. On some tracks I will apply the flip-side of this tactic and roll off the top end, but one must be more careful with this. A lot of times it’s hard to tell when to stop rolling of the top and it’s easy to end up with a very flat sounding mix.

Next I will start to place certain instruments in certain frequency ranges. The video in this post goes over this as well. The electric guitar often encroaches on the frequencies that I plan on using for the bass guitar so I will cut some of those frequencies out of the electric guitar signal (typically somewhere around 200-300 Hz). The definition of an electric guitar, and most instruments for that matter, usually happen in the 2.5 kHz to 7 kHz range. This is also known as the presence range and these are the frequencies that humans hear “best.” That makes this band of frequencies very important, because not every thing can be there at the same time. Spend your time experimenting with you balance here in these frequencies. I tend to boost electric guitars on the low end of the presence range and save the bulk of it for the vocals. I also boost the electric guitars up around 7 kHz to let them sparkle and sizzle a little.

That’s the gist of it! The important thing is to be conscious of where in the frequency spectrum each element of the mix is going to live, and then of course getting good levels. Listening to a mix at very low volumes can often tell you what is hot in the mix and what is being drowned out and masked, I do this often when getting a balance.