January 17, 2014

Mastering the EQ Sweep: The First Equalization Trick You Need and Will Use Forever

Guest Blog By Steven J Goldman. Steven is the CARA Award-Winning engineer for Four Legs Records, a professional recording, mixing and mastering studio in upstate NY. He is an experienced producer of Rock, Metal, A Cappella, Indie, Hip-Hop and Electronic styles, as well as a composer and performer. Connect with him at www.fourlegsrecords.com, and at www.facebook.com/fourlegsrecords.

Equalization, commonly referred to as “EQ,” is an altering of a sound’s level at specific frequencies, rather than a straight-up change in overall volume. You’ll find equalizers in every digital audio workstation, on every console, and on nearly every PA system in existence.

Professional audio engineers use EQ to carefully sculpt the sound of their recordings. They can boost (raise) or cut (lower) certain frequencies in various tracks in order to enhance characteristics they wish to bring out or downplay. For example, they can roll off low frequencies in a vocal track to help it stand out in a dense rock mix. Or, they can boost the midrange frequencies in a bass track to enhance the “pick” sound. They have specific hardware or software equalizers, each with a characteristic sound / purpose / color / flavor / odor, or what have you. Most of the equalizers that professionals use come with a modest to hefty price tag, and require a discerning ear to truly appreciate.

But in the world of home recording, basic EQ ends up being mainly used as a ‘Band-Aid,’ for cleaning up tracks that could not be recorded with an ideal microphone or in an ideal environment. Maybe you don’t like how ‘muddy’ your voice sounds, or perhaps your electric guitars sound too ‘sharp’. Instead of blindly applying settings you’ve seen suggested somewhere, it’s best to learn to use your ears and tailor the EQ to your specific source. We can use an EQ sweep in order to do this.

Here’s the idea; you have a track that sounds bad to your ears, but you’re not sure what exactly is bothering you about it. The most likely reason - a certain range of frequencies are too prominent in the signal. We will need to cut them, at least by a little. So what we need to learn is how to find exactly what frequencies to cut. I engineer all of my mixes in Cakewalk’s SONAR X1, a digital audio workstation with many built-in tools. Though I usually run a number of boutique EQ’s, let’s use SONAR X1’s built in equalizer to demonstrate the process.

In order to find what frequency to cut, we will create an EQ boost that is very sharp (lots of gain - we’re making it loud, adding anywhere from +8 to +15db). We also want this boost to be very narrow, because we want to later pinpoint a specific offending frequency. The width of a boost/cut is known as “Bandwidth” or “Q,” and the higher your Q, the more narrow the cut/boost (yes, it is opposite day)! Be sure to use a “peak/dip” EQ band, as opposed to a shelf or a bandpass. The peak/dip type eq is usually denoted with a ‘hump,’ and appears quite pointy when visually represented. Ignore the shelf/bandpass stuff for now; just pretend they don’t exist. In SONAR’s equalizer, we would select the peak/dip option from the “filter” section. See Fig. 1 for an example.
Figure 1. Creating a sharp, narrow EQ boost. Look how pointy it is!

Next, while listening to the problem track, we slowly drag our EQ band up through the frequencies until it sounds really bad (see fig. 2). If the track was too sharp, we’d drag the band around until it made that exact sharpness unbearable. If the track was too muddy, we’d drag the band to the frequency that makes that muddiness the most prominent. We’re not setting the EQ on a predetermined frequency; rather we are fitting the EQ to our unique source.
Figure 2. Dragging the boost until things sound... just awful.

Now that we know what frequency band made us most dislike our track in the first place, we simply need to reverse the boost into a cut (see fig. 3). We use our ears again here, and only cut as much as we absolutely need to. There are no steadfast rules here, just learn what sounds good. Start with mild cuts and go further if necessary. Listen, as our ugly duckling of a track transforms into a more pleasing duckling that swims gracefully on top of our mix!

Figure 3. Reverse the boost unto a cut. Turn that frown upside down!
Lastly, we just need to widen our “Q” or bandwidth as needed (see fig. 4). The lower the Q, the wider the cut/boost will be. Again, we use our ears, and leave it only as wide as we need in order to achieve our desired sound. In general, cuts should be narrow and boosts should be wide, but nobody can force us otherwise! 

Figure 4.Widen your Q’s! And cross your t’s.

There are hundreds of equalizers and tricks that are tailored to a world of different scenarios and sources. But the sweep and cut is ubiquitous. You can use this technique in every scenario, bar none. Live, at home, or in studio, corrective EQ is all about using your ears to clean up anything that isn’t ideal. If there is a single equalization technique to remember, this is the one.
Related Posts Plugin for WordPress, Blogger...