The Parametric Equalizer – Your best friend

The parametric equalizer is one of the more useful tools we have as audio engineers. It's a sound shaper, a tool that allows you to shape and mold the recorded sound to your needs.

It's uses are various, from adding a little air or presence to a track before it gets recorded to repairing badly recorded sounds in the mix.

Many different standpoints are on the use of EQ, just like on every facet of the recording and mixing process.

Some people would rather change a mic to one that has more presence instead of adding a little presence boost at 5Khz.

My standpoint on this is that if you have an equalizer that works well for you, why shouldn't you use it? In today's world, a lot of stuff is recorded in less than ideal situations and sometimes the only way to salvage badly recorded tracks is with the creative use of EQ.

And no EQ is better than the parametric equalizer.

The parametric equalizer give you the most amount of parameters and choices to play around with. It's setting include:

Herts – Which frequency band you are either going to cut or boost.
Gain – how much, in dB you are going to cut or boost.
Q – How narrow or broad your boosts are going to be.

Q, in the old days stood for quality. The narrower the cut, the better the quality of the cut, since it was affecting less of the neighboring frequencies. So a high Q means a narrow Q.

On top of this the parametric equalizer usually has a selection of frequency bands to choose from. A typical analog mixer usually has four frequency bands, one for lows, one for lower mids, one for higher mids and one for highs. The mids generally have a bell curve that you can boost or cut and the low and high bands have a shelving curve that increase the gain of every frequency either above or below a certain frequency.

Frequency breakdown

Mids, highs and lows? I only see numbers on this parametric equalizer you keep talking about!?

Well, let's break down the general frequency categories and put those numbers inside.

Lows are generally thought to be below about 200Hz.

Low Mids are from 200Hz to around 6-800 Hz.

High mids are from where the low mids stopped and go up to about 4Khz.

All that high end sheen(I like the word sheen) is from 4Khz upwards.

So by breaking the spectrum down into four categories it's easier to articulate what is needed from each category.

We've got words like Brilliance that applies to the higher frequencies, as well as Air that belongs in the topmost frequencies. Then we have slang such as Presence that's around 5Khz, and Boxiness that's around 4-600Hz. Check out my mixing tutorial on boxiness if you're having trouble with these cardboard frequencies.

It's useful to get into the lingo of EQ in order to become a better communicator in the studio.

Tips on using the parametric equalizer

Just like I touched upon in the 3 principles of Eq'ing we have a few ways of using EQ.

By boosting a signal we try to add or enhance some characteristic of a sound we want to stand out.

By cutting we are usually trying to repair, or cut out unwanted sound from a signal. By using the Q we can decide how narrow or broad a boost can be, and how noticable a cut or boost will be.

If you have a problematic frequency the best way to find it is to turn the Q all the way narrow and boost a frequency band as much as possible. Then you can scan the spectrum until you hear the unwanted frequency pop out. Now you can cut the frequency and adjust the gain and Q according to your needs and taste.

When trying to add some sweetness to an instrument it's best to boost fairly broad and scan around the frequency spectrum and see if the instrument jumps out at you.

Maybe the guitar needs a little bite and it pops out at 2Khz, or it needs a little weight and you get that chug,chug sound at 500Hz. Obviously, depending on the genre you are going to equalize differently

Let's take the kick drum as an example.

In rock music you want to have a fairly natural kick drum sound but you still want the sound of the beater coming through. Thus, you boost around 1-2 Khz, maybe even a little higher, depending on the drum. And you have a fairly broad boost since you don't want it to sound abnormal in context to the rest of the song.

But in metal you do it differently.

In metal there's a chracteristic click to the kick drum that's easily accented by the use of creative equalization. The click is accented by boosting at a higher frequency and sometimes with a very narrow Q.

Let's use Logic's parametric equalizer to make these two audio samples. The first one has a wide frequency boost at 2.5 Khz and the second one has a metal spike at 4Khz.

rock kick drum

Rock kick with 2.6Khz boost

metal kick drum boost

Metal kick with a 4.1Khz boost

So you see how much creative EQ can affect the sound of the genre. The first click wouldn't exactly cut through in a thrashing metal track, but it is certainly enough in a rock track.

Conclusion

The parametric equalizer can be your best friend if you use it correctly. For a mixing engineer it is often the first tool - in conjunction with compression - that he uses. We use equalization to filter out frequencies, add sparkle and repair badly recorded instruments.

As said before, although many engineers get away with using alternative methods to EQ, the fact is that it is the best tool to mix your songs so they glue together.

With EQ you are able to sculpt and place every instrument and track so they sound as a whole. Next time you find yourself confronted with an equalizer, use these tips and tricks to further enhance your audio production.

Use the parametric equalizer for eq'ing the vocal

Use this EQ tip for dealing with muddiness in your mixes

Make EQ'ing multiple tracks simpler with routing