Home → Principles of Equalization: How to EQ Your Music + Different Types of EQ’s

Marco Sebastiano Alessi

May 23rd, 2022

Principles of Equalization: How to EQ Your Music + Different Types of EQ’s


You start making music having no idea what audio equalization is and how to implement it in your mix; this is part of the standard journey of every new music producer.

Then, after some time, you begin realizing other people’s music sounds better than yours because each frequency is more defined, and the overall sonic feel is more pleasant. Eventually, you start wondering why your music doesn’t sound like that.

Understanding the importance of equalization (EQ) comes with practice. By actively listening to music and shaping your music production to reach industry standards, you’ll realize the importance of this fantastic tool and how to use it efficiently. The principles of EQ for beginners are a crucial step in the career of music producers and audio engineers.

Today we’ll focus our attention on the principles of equalization: what it is, the different types of equalizers, how to use an equalizer, and why it’s crucial for your mix. By the end of the article, you’ll have all the information necessary to make good use of this fundamental effect and choose the best EQ software based on your needs.

Let’s dive in!

EQ Explained: What Does EQ Mean?

Let’s start with some EQ basics. Equalization allows you to adjust the levels or amplitude of each sound frequency. In this way, you’ll be able to create a balanced mix where each sound is clear, and the frequencies don’t interfere with each other.

Everything we hear is a sound wave that vibrates at a specific frequency. These frequencies are intercepted and translated by our brains, which identify them as particular sounds.

Now, different sounds vibrate at different frequencies. For example, with music, we use the frequency of notes to tune instruments or identify a note. However, all musical instruments produce many frequencies at once, aside from the pure sinusoidal tone that defines them.

These frequencies are what make each musical instrument unique because they’re the result of a variety of factors that are almost impossible to reproduce.

Essentially, the harmonic content contained within each note interacts with the rest of the soundscape you created, bringing your compositions to life. A note’s frequency is measured in Hertz and Kilohertz (Hz and kHz).

How Does An Equalizer Work?

Principles of Equalization

Sound frequencies interact and interfere with each other, and this can cause distortion or unwanted noise. This is when EQ comes into play.

Equalization allows you to adjust individual frequencies or a group of frequencies by enhancing or mitigating their impact on the overall sound. Therefore, EQ enables you to optimize each sound frequency to ensure the soundscape created is perfectly blended.

What Is EQ In Music?

How to equalize music is a fundamental step in the career of a producer because it’s a clear sign you’re mastering your craft and aiming to make your music sound its best. EQ affects all aspects of music production, from shaping the sound of single musical instruments to mixing and mastering a track.

Understanding EQ in music production is a slow process that starts with getting the suitable audio recording and listening gear, followed by hours and hours of listening sessions. The first thing you need to ask yourself is how you want your music to sound.

Once you clarify the sonic atmosphere you want your music to have, you can start learning more about EQ music production, EQ mixing, and all the tools to help you achieve the sound you have in mind.

By using an equalizer and removing or boosting specific frequencies, you’ll dramatically change the way your music sounds. Not only will your song sound more professional, but by adjusting the frequencies, you’ll see the song’s mood will take different directions, depending on which frequency bands are more prominent.

It takes time but understanding an equalizer and the way it can improve your sound will enhance your tracks in ways no other effect can.

How To EQ During Mixing

If you’re a music producer, initially, the mixing session will look like the most tedious part of making music. In time, this aspect of the creative process will have an increasingly crucial role in the quality of your output because it defines your sounds as much as your sound library does.

The EQ process is an integral part of the mixing chain. It’s a must-have for audio engineers and producers alike because of the impact it can have on the song’s overall quality. If used correctly, musical instruments will sound more blended, the loud frequencies will be less prominent, and the low frequencies will be loud and clear.

How do you achieve optimal audio quality during the mixing session?

Broad Boosts and Narrow Cuts

First of all, a well-known mixing technique involves using broad boosts and narrow cuts to shape sounds. By adding EQ to a wide range of frequencies, you’ll create a subtle emphasis on specific frequencies without abrupt changes in the audio spectrum.

Narrow cuts are useful because they help remove unwanted sounds that don’t blend well with the rest of the frequencies. Removing too much will eventually create a void in the audio spectrum, which will make the song sound hollow.

Cutting or Boosting First?

Some engineers opt for boosting the sound first and then use surgical EQ to make changes to narrower frequencies. Others do exactly the opposite. Which technique should you use when mixing your tracks?

Personally, I boost the tracks first, the reason being that I want to enhance the frequencies I’m interested in emphasizing before I start working on more subtle changes. In this way, I can hear the track’s potential right away and work towards that goal.

On the other hand, working on more surgical EQ first will help you maintain a more genuine sound and target unwanted frequencies more precisely. Again, both options are valid and widely used, so the best option might be to try them both and see which one fits your workflow best.

Use A Narrow Q Boost To Find Unwanted Frequencies

A great technique to find nasty frequencies is by using a Q boost to magnify the unwanted noise and remove it afterward.

Once you become familiar with the EQ plug-ins, you can use them to target a narrow range of frequencies utilizing a Q boost. By boosting them considerably, you’ll start hearing all sorts of harmonics and resonances that would otherwise go unnoticed.

Once you have identified the frequencies you want to remove, you can mitigate them or remove them entirely using the appropriate EQ tools.

How To EQ During Mastering

The final step that’ll bring your song to life is the mastering process. When mixing is done properly, audio mastering is a smooth and fun process that can add more clarity and vibrancy to your track. Conversely, if the mix is not perfect, getting the right sound will be a challenging job, to the point you might consider going back to the mixing phase.

When mastering, EQ is all about reaching the appropriate loudness level and tonal balance you envision for your piece. To achieve these results, you need to focus on some crucial factors.

Here are a few tips about How to Master a Song – spend just 5 minutes to read it!

Set The Audio Level

Are you publishing your album on CD or just making it available digitally? Depending on your album’s format, the loudness level is different: -9 integrated LUFS for a CD or -14 LUFS for the most common streaming platform. LUFS stands for Loudness Units Full Scale, and it’s a new way to measure the loudness of sounds.

Knowing the targeted audio level before commencing mastering is crucial because it’ll impact the way you approach the process. Getting the proper audio level will make your song sound professional on all audio playback devices and help you reach standard industry quality with your tracks.

Issues With Low Ends

Low ends are always an issue. They’re either hard to hear, too loud, have conflicting frequencies, or nasty harmonies. If you’re a music producer and want to do everything on your own, rest assured the low frequencies are the ones you’ll have to invest more time on in order to get your sound just right.

The process changes depending on the music genre you work in, but the principle is the same for everyone. You have to enhance low frequencies while leaving enough headroom to preserve the song’s natural feel.

This means cutting off some frequencies that don’t have an impact on the song’s sound while amplifying the ones that blend well with the rest of the mix.
You’ll need to split the lower audio spectrum into different bands and work on each of them separately, but getting the low frequencies right is the key to publishing a high-quality audio track.

Use Reference Tracks To Add Character and Clarity

Reference tracks are important because they give guidance. Whether you’re an audio engineer or an artist, having a result in mind will give you an idea of the mastering effects you’ll need to achieve a similar effect.

Once again, focus on each band separately to create an enveloping soundscape. Boost high frequencies above 10 kHz to make the song crispier and more vibrant. Bring focus to the mid-band by boosting it until the main sounds of your track are prominent and rich.

It’s important not to add too much EQ in this phase, as it’ll most likely cause unwanted distortions or unbalanced harmonies. You’ll soon realize EQ mastering is a delicate process that’s made of minor variations rather than drastic changes.

When To Use EQ

Equalization is a lifesaver for music producers, as well as mixing and mastering engineers for various reasons.

Regardless of the music genre, you work in or whether you make music exclusively on your laptop or record real instruments, EQ can help you shape your sound and ensure each instrument can be heard in the way you envisioned it.

The more complex a composition, the more likely you’ll need to use some form of equalization. Two main issues may arise in your recordings.

  1. Overlapping frequencies. This happens when two instruments play notes so close to each other that their sound frequencies sound muddy and indefinite. This is common, especially with lower frequencies.
  2. Unwanted sounds. Some musical instruments have resonances that may work well when played on their own but don’t interact well when there are other instruments involved. EQ can mitigate or remove specific resonances while leaving the rest of the frequencies untouched.

EQ parameters

EQ parameters are what you’ll use to enhance or remove specific frequencies in your audio. Common parameters include the following:

  • Q: also called “quality factor,” this is the parameter that allows you to determine and adjust the bandwidth, i.e., the range of frequencies you want the equalization to affect. This is a fundamental parameter as you can decide which frequencies to edit and which ones to preserve.
  • Gain: as with many other effects, the gain allows you to adjust how much you want the EQ to affect the selected frequencies. You can increase it or decrease it until you reach the optimal result.
  • EQ filter type: we’ll talk more about this below, but essentially, EQ filters are defined by their shape, and their shape affects the frequencies.
  • EQ filter slope: the steepness determines which frequencies are mitigated or cut off. As you’ll see below, you can fully customize the filter curve to your needs.

The Different Types Of Equalizers

Equalization requires adjusting your mix whenever you add a musical instrument. That’s because the balance between each sound will change depending on how many and which instruments are playing simultaneously.

Generally, frequencies are divided into different bands called bass, low-mid, mid, high-mid, and high. Each band defines specific frequencies based on their Hz or pitch. You can manipulate each band separately, ensuring you’ll make adjustments only to the frequencies you’re targeting.

The equalization tools used when mixing and equalizing music are called filters. Filters are defined by their shapes: a bell or a shelf shape will have a different impact on sound manipulation.

Let’s take a look at the most common equalization filters.

Peak EQ

This type of EQ is one of the most commonly used because of its versatility and highly customizable features. Using the parametric, bell, or peak EQ will allow you to focus on a specific bandwidth and either cut or boost certain frequencies. The name of this filter comes from the bell-like shape created by the visualization of the filter.

The wider the bell, the broader the frequency range the filter will have an impact on. Conversely, a narrow or high bell will affect only a small number of frequencies. The shape of the bell is defined by the value “Q” we discussed earlier.

What makes this simple EQ filter so popular is its ability to target both a wide range and a small number of sound frequencies, depending on your needs. You can use the former to change the overall sound of your track and the latter to target specific audio frequencies.

High Pass/Low Pass Filters

Whoever named these filters in this way purposely wanted to complicate people’s life. Basically, the high pass filter lets you cut all low frequencies from a certain point onward. The low pass filter does the opposite, removing all high frequencies from a predetermined cut-off point.

Someone tried to make more sense out of the confusing naming situation by calling the high-pass filters low-cut filters and low pass filters high-cut filters. You can use whichever name makes more sense to you.

High Shelf/Low Shelf Filters

These filters are “gentler” than the pass filters as they don’t cut off all the frequencies above or below a certain threshold but rather smooth or reduce the targeted frequency range to improve the overall sound quality.

You can use the high shelf filter to boost or cut the high-end frequencies. Generally, this filter is used to enhance frequencies above 10kHz and make songs more vibrant.

The low-shelf filter is commonly used to mitigate unwanted noise from percussion or microphones. Audio engineers use it frequently to reduce sounds typical of recording sessions while maintaining the natural soundscape of the room untouched.

Final Thoughts

I hope this article helped clarify the basic concepts of sound equalization.

Adding EQ to your workflow will increase the audio quality of your tracks dramatically by adding clarity to your mix. However, make sure you don’t overuse it, or you may end up cutting off frequencies that are beneficial to the soundscape you’re creating. With EQ, as with many other tools, sometimes less is more.

Good luck, and stay creative

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