Learning how to mix and master professionally requires the use of equalization. Equalization (EQ) in its most basic form is a process that allows the mixer to manipulate the frequency bands of a sound. The mixer can boost or cut any frequency they wish. Equalization plugins can be used to add bass to a sound, to make it more crisp, or to thicken it up by adding mids. This can sound very confusing to a beginner but the process is actually quite simple. Have you ever been riding in your car and used the radio knobs to turn up the bass or treble? If so, then you have used equalization. The radio in your car probably has 2 bands you can manipulate: Bass (the lower frequencies), and Treble (the higher frequencies). The process of equalization in audio engineering is the exact same except it has many more bands to manipulate and the range of the bands can be adjusted.
Let’s start with the controls on an EQ plugin. Most EQ plugins will have several knobs for each band:
- - Frequency – this knob controls what frequency will be affected
- - Q- this knob controls how wide or narrow your boost/cut will be to the frequency
- - Gain- this knob affects whether you will boost or cut the selected frequency.
- - Using these controls you can manipulate any sound however you would like. An EQ plugin will typically have 2 filter controls as well: A Low-Cut Filter(High-Pass) and a High-Cut Filter(Low-Pass). These filters do exactly as their names suggest. A Low-Cut(High-Pass) filter will cut all of the lows below your selected frequency and let all of the highs above that frequency pass through the plugin unprocessed. A High-Pass ( Low-Cut) filter does the exact opposite and cuts all the highs above a certain frequency while letting all the lows below your selected frequency pass through the plugin unprocessed. Some EQ plugins may also have a Mix knob. Using this knob you can blend the “dry”(unaffected) signal with the “wet”(affected) signal. This can be very useful for adding a bit of a natural sound back into the signal if your EQ has made the sound unnatural.
EQ is one of the most important tools to use while learning how to mix and master. This article has but shown you the controls that will be found on an EQ plugin. If you wish to learn more about frequency bands, how to use the plugin, which frequency bands to affect, how to EQ correctly and more about the general process of using an equalizer please view my other articles covering the topic of equalization.
-The above image shows an instance of the award-winning plugin “Pro-Q” by Fabfilter. This particular instance of the plugin is using a High-Pass filter to cut some of the lows from the signal. It also has a notch cut at around 95 hz which we can assume was a problem frequency in the context of the mix. The last band is applying a wide boost to 2.2Khz to add some clarity to the sound. This EQ plugin is both very powerful and very precise. If you are interested in seeing Fabfilter’s Pro-Q in action please visit http://www.fabfilter.com/products/pro-q-equalizer-plug-in