Understanding Studio Equalizers

Studio Equalizers in short are sliders that control the level of frequencies in a recording. They are important for accurately recording sounds into a microphone because it will not always perfectly translate what it hears. For example, if you are recording a cello, you will want to make sure that you fully capture the low frequencies that the instrument possesses. If you are recording a more unique instrument such as your voice, the EQ settings will vary depending on the person.


 In this tutorial, I will show you what the different sliders do, and how to manipulate them they way you want.

Below is an example of a basic 10 frequency equalizer. You can find equalizers with many more frequencies, but all of them work the exact same way. As I mentioned earlier, an equalizer controls the level of the frequencies in a recording. What do I mean by that? For example, if I am working with a drum track, and I want to increase the amount of bass, I would raise the lower sliders on the equalizer. If you look at the example below, you will see that below each slider is a number. Each slider controls a different frequency, and the frequency on an equalizer is measured in hertz. The lowest frequency [31.5hz] controls the lowest frequencies in a recording, while the highest frequency [16000hz] controls the highest frequencies. So, when you are adjusting the sliders, remember that the lower the number, the lower the frequency it controls, and vice versa. Now if you scroll down, you will see and hear examples of an equalizer in action.

Before you listen to all the EQ samples, here is the drum recording I will be using as an example throughout the lesson without any changes to the EQ, just like you see in the image above.





Bass Sliders

The sliders to the left of the equalizer control the bass, as you have learned. Below is a visual and audio example of what happens when you increase the bass:

Now here is what happens when you decrease the bass:

So, as you heard, the lower sliders control the bass. Keep in mind though that as you move slowly to the right on the sliders they begin to affect the mid-range of the recording, so in this case, the snare drum.

Treble Sliders

These sliders affect the high range of a recording, so in this instance, the high-hats. Take a listen here for what happens when you increase the high frequency sliders:

Now let's decrease the amount of treble:

After listening to those, you probably heard that the high-hats sounded different, but also the snare drum. (only slightly though)

Mid-Range Sliders

These sliders affect the mid-range frequencies of a recording, so they affect a bit of the bass and a bit of the treble at the same time. These sliders aren't as straightforward to use because they don't affect the sound as dramatically as the high and low frequency sliders, but they are still important.

Here is what happens when you increase the mid-range sliders:

Now here is an example of making a decrease in the mid-range sliders:

As you heard from those two samples, the middle sliders affect the mid-range frequencies the most, but also affect the upper and lower ones as well.

Using EQ in Music

When using an equalizer, you can use it not only to accurately record sound, but also manipulate it to create an effect you may want for a particular song. If you intentionally want the bass boosted on a drum kit, or the treble dropped in the bass guitar part that you are recording, it would be smart to originally record the instrument to its original quality and then manipulate the EQ in your music software. Doing so will make it easier to adjust the settings to the way you want them to. If it isn't possible to manipulate the EQ after your recording, at least record a version with accurate EQ just in case you might need it for later on.
Below is a sample from a song I wrote, and how I intentionally played with the EQ to get the "stereo" effect.
While you are listening, try and figure out how I manipulated the sliders, so ask yourself questions like, "did she increase or decrease the bass over time?" This is good practice for your knowledge of how all the sliders on an equalizer work.




So as you heard from that demo, the music seemed to "come to life" in the sense that you felt as if you were making a transition from listening to a radio to actually being in the studio listening to the performers.
For those who challenged themselves to see if they really understood equalizing, here is what I did to get this effect: I started off the song with all of the mid-range and treble sliders on their highest setting, and turned the bass sliders all the way down to their lowest setting. This created the stereo effect you heard in the beginning. Over the course of the piece, you hear the instruments become clearer, and what I did there was I created a gradual transition from the extreme EQ settings to level 0, so all the instruments sound the way you would hear them live. *Note that I used software instruments instead of a live recording, so the most accurate setting for them was 0. EQ settings vary depending on live recordings.

Now that you have hopefully grasped the concept of equalizing, you can now go out and do sound engineering like a pro.


*Reminders about Equalizing

~EQ levels vary depending on the sounds you record
~ There are equalizers that have different amounts of sliders, but they all work the same in the sense that they manipulate the frequencies of a recording
~ EQ frequencies are measured in hertz

Click here for EQ practice