Before a song makes it onto your playlist, it most likely was mixed and mastered by an audio engineer whose job optimize the sound on as many devices as possible. They don’t know if you’re going to be listening on headphones or speakers, so they cast a wide net to compensate for most situations. Most engineers know how to EQ, so the music sounds just fine in most scenarios. But if you know what you’re doing, you can really make your music shine with a few simple tweaks.

Why should you EQ your music if a professional engineer has already done it? Well, there are two main reasons why you’d want to, and they’re not mutually exclusive. Most people EQ because of a combination of the two.

  1. Preferences. It should come as no surprise to you that everyone hears things a little differently, because of the physiology of the human ear. What sounds good for most people could sound even better to you, if you know what to do. And we all know you’re the only person that truly matters, right?
  2. Faulty equipment. Nothing is perfect, and sometimes your headphones or speakers might have a hardware quirk to them that’s too annoying to just leave be. If it’s not too serious, then chances are you can account for that quirk when you EQ. It’ll be like it was never even there.

What is an EQ?

Before we get into the gritty details, it’s probably best to go over what an EQ is. EQ stands for equalization and, according to Wikipedia, is defined as “the process of adjusting the balance between frequency components within an electric signal.” That’s a pretty bomb definition, primarily because of the word “balance.” A good EQ is all about finding the perfect balance between the frequencies in your music (and knowing how to manipulate that balance to get what you want).

On a practical level, if you’ve ever been around audio equipment of any kind, you at least know what an EQ looks like. Most people will recognize the bass or treble knobs in the car or on some speakers. Those are basic EQ dials. They get a little more advanced once you dip your toe into high end recording equipment and receivers. One of my earliest memories is messing around with the EQ sliders on my mom’s old receiver mid-Barry White set. By sliding or turning these settings, you can control the output of a given frequency range, letting you tweak the sound coming out from your equipment.

The basics

Now that we know what an EQ is, we can start getting into the fun stuff: how to EQ. There are two parts to an EQ: center  frequency and bandwidth. Center frequency might sound complex, but it’s just selecting the specific frequency that you want to adjust.Bandwidth, also known as Q, refers to how narrow the selection is for the adjustments that you want to make. If you go into a car and see the bass and treble knobs, those usually have a very broad Q, which looks like a small hill when you’re adjusting it. But if you want to target a very specific frequency range, then having a more narrow Q will let you achieve this. Visually, this will look more like a needle.

A screenshot with labeled wide and narrow Q.

On the left: a wide Q adjustment. The right: narrow Q.

A method to the madness

There are two ways to tweak your sound when learning how to EQ. The first is to make the target frequency louder by raising the volume  (amplitude) of a specific range. This is called boosting. It makes sense if you think about it, you’re just boosting the output of something that you want to hear more of. On the flip side, you can also decrease the output of a specific frequency range for something that you want to hear less of. This method is called cutting.

Cutting is better than boosting

As a general rule of thumb (actually it’s more like a rule), cutting is better than boosting. If you boost too much you can introduce distortion, which is the opposite of what we’re trying to accomplish here. Boosting also tends to result in a loss of clarity and, in some cases, can result in some weird phasing problems. A visual analogy to the cut/boost relationship would be like turning up the ISO on a camera. It makes the image brighter but simultaneously makes the image grainier.

In short, it’s better practice to boost the master output and then cut the frequencies that you want to adjust. If done correctly, this will give you the same result while keeping everything below the distortion threshold. There’s a saying in audio engineering that applies when EQ-ing your own music: cut narrow, boost wide.

Trust your ear!

Sound is a very personal experience. And we mean that both mentally and physically. I’ll never be into mumble-rap, and your ear will never be exactly the same as mine. Moral of the story is that things sound different to each person, so everything from here on out, regarding how to EQ, is just a guideline to help find what works best for you.

Know what you’re changing

Whether you want more bass or less cymbals, you should know more or less where their frequency ranges lie. The chart obviously doesn’t include every sound effect and instrument ever made, but it’s a good generalization.

A chart showing where common music notes reside in the range of audible frequencies.

Most fundamental notes for common instruments lie below 1kHz.

Notice how almost all of the instruments lie under around 10 kHz, save for cymbals and hi-hats which can go a bit higher. Sub-bass is usually between 20 Hz – 60 Hz, and though it’s hard to hear: you’ll physically be able to feel the air being pushed if you have a large enough woofer. Then there’s the kick drum and bass guitar fighting over space anywhere between 60 Hz – 250 Hz.

Your average electric guitar and both male and female vocals (with obvious differences) can be found roughly between 80 Hz and 1 kHz. One area that you should pay special attention to is the range between 250 Hz and 1 kHz. As you can see there are a lot of instruments that can in the range (and we only put a few), so adding too much emphasis here can make a song feel muddy, while taking too much away creates an empty, hollow feel.

Make Dr. Dre proud.

Adding emphasis to anything around 2 kHz usually makes the impact of picking guitar strings easier to hear, while anything in the 6 kHz – 16 kHz range can give music a kind of treble heavy airiness. Obviously the reverse as well, and bumping anything in the 20 Hz- 250 Hz range will give you a thumping low-end that would make Dr. Dre proud.

If you want to test how good your hearing is, we generated a few sine waves down below. Humans can technically hear anywhere from 20 Hz – 20 kHz, so we made four that span the entire range (20 Hz, 250 Hz, 2 kHz, 16 kHz). Just a heads up, we’d recommend turning down the volume for the 2 kHz sound.

Sub-bass

Bass

Midrange

Highs

Find the bad frequencies

Rather than looking for the parts of a track that you like and then boosting them up, find the parts of the track that bother your ears. Then, cut them down. Usually, you can do this with a high Q (narrow), and sweep through until you find a noise that’s particularly harsh or conflicts with something else that you want to have more prominence. Then, you can lower the Q and cut that part out.

This gets rid of the unsavory aspects of your music without the side-effects that come along with boosting (introducing noise and distortion). When you’re done, you can raise the overall master volume up to a pleasing volume and still have a natural-sounding mix.

Get Rid of the Extreme Highs (Add a Low-Pass Filter)

A demonstration of a low-pass filter.

A low pass filter preserves everything below a set limit, and cuts everything over it.

Some audiophiles will tell you that they need headphones that can reproduce sounds well above 20 kHz, which is B.S. Humans can only hear up to 20 kHz, and unless your audiophile friend is part-dolphin, they can’t hear a damn thing that goes above that frequency. Want proof? Just download any dog whistle app and see how far up you can push it and still hear the tone. Can you even hear the tone that’s playing down below? To be completely honest, I can’t either, so I’m just going to assume my computer did what it was supposed to when making this.

Now there are some arguments that having that bit of space helps with the overall sound of the music. For better or worse, we’re not going to get into that here, and unless you have one hell of a trained ear (and you’re very young), you simply won’t hear it. Just cut all frequencies above 20 kHz-ish to get rid of excess highs that you can’t even hear. This is called adding a low-pass filter. Once you’ve done that, just tweak the points until those cymbals are just how you like them. Remember, even if you’re just learning how to EQ, trust your ear!

Get Rid of the Extreme Lows (Add a High-Pass Filter)

A chart showing a high pass filter.

A high pass filter preserves the sound above a certain cutoff, attenuates everything below it.

Just like how there’s no point to having anything above 20 kHz, it’s really hard to hear anything below a certain frequency range as well, especially if you don’t have a fire sub-woofer and some bass traps. So just cut your EQ curve at around 50 Hz. This is called adding a high-pass filter.

Use presets!

Some apps/software come with a built-in preset, these are great for learning how to EQ. The resources are there, use them! They’re there for a reason and are generally made by professionals who just might know what they’re doing. What I usually do is pick a preset I like and then make minor adjustments to that, instead of starting from scratch every single time. Some apps, like Neutralizer for Android, make it super personal by letting you do a hearing test beforehand to see which frequencies matter the most to your ears. For desktop, there’s also Voicemeeter by VB-Audio and True-Fi by Sonarworks. There’s nothing wrong with using a preset, but if you want to dig deeper, beyond just learning how to EQ, keep these tips in mind and you’ll be fine.