What is EQ?: How to Improve the Sound of Your Headphones

Buying the best headphones in your budget is only half the battle. If you want great sound from your headphones, there are a lot of other things you will have to do. Although some of it involves buying more, often expensive, hardware, there are ways to improve the sound on your headphones without spending any money.

If you’ve grown up playing around with media players in the 2000s, you know about EQ, a.k.a. Equalizer. It’s a software feature that lets you adjust the intensity of different frequency ranges so you can get better sound from your speakers and headphones. Here’s how EQ works and how you can use it to make your headphones sound better.

Understanding how sound works

Before we get to EQ, it’s important to understand how sound works. To put it simply, sound is made by vibrations. These vibrations originate from the source and travel, ultimately, to your ear in the form of waves. The sound differs based on the frequency of the vibrations. The data in the sound file, like an MP3 file or an audio/video stream, contains the different frequencies needed to recreate the sound. When you use a headphone, this data of the sound from the source, i.e. your computer, phone, or anything else you’ve plugged them into, is converted into vibrations.

Headphones all sound different because they’re all made to convert sound data into vibrations a little bit differently. Human ears can typically hear sounds in the 20Hz to 20KHz range. These are typically broken down into lows (20Hz-200Hz), which we colloquially refer to as bass, mids (200Hz-2KHz), and highs (2KHz-20KHz), also known as treble. There’s no unanimous agreement on what the exact frequencies are that define each of these ranges, but lows come with a thump, mids typically sound pleasant, and highs sound a bit screechy.

Now, these frequencies and the way we hear them will depend on two factors mainly. One is how they’re defined in the sound file. For example, bass-boosted remixes of songs have the bass frequencies tuned up for that extra thump, which can sometimes be unpleasant. The other factor is the sound of your headphones have. Some are neutral, which means they do little to enhance any of the frequencies. Some headphones can be bass-heavy, which means you will get a more booming sound, while some are treble-heavy.

Typically, the cheaper headphones lean toward either extreme of these frequencies. At the same time, not everybody will like a neutral pair of headphones, even though they’re considered the most accurate. All of this leads us to the equalizer, better known as EQ these days.

Read more: Wireless vs. Wired Headphones: Which is Better?

What is EQ?

Equalizer, or EQ, is a step between the sound source and the audio device, i.e. your headphones. It’s a way to adjust the different frequencies of a sound signal, modifying it before it is output through your headphones. It’s a software-based way to increase or decrease the intensities of different frequencies in a sound signal, although hardware EQ solutions exist for professional purposes.

Why use EQ? I like to use the equalizer because I have a sensitivity to treble, which means my EQ is almost always set to drown the higher frequencies. Some folks may like bassier sound, which can also be achieved with EQ. Essentially, if you’re not happy with how your headphones sound, you can use EQ to tune the sound to make it much closer to your liking.

A graphic EQ presents you with a bunch of sliders assigned to different frequencies, called frequency bands. The frequency you select to adjust is typically called the center frequency. This is the frequency on the label of each slider. You can adjust these sliders to change the levels, a.k.a. the gain, of each frequency band to enhance your lows for a bassy sound signature, play around with the mids, or adjust the treble by changing the high frequencies. The bandwidth is the width of each frequency band. The higher the bandwidth for each frequency band, the fewer sliders your EQ will have. More sliders mean lower bandwidth to adjust for each frequency band, which means more control over the more minute parts of the sound.

Now, an EQ itself can differ a lot. It can be a systemwide app that applies your frequency preferences to every bit of sound coming from your computer or phone, but some operating systems like iOS don’t support it. On the other hand, if you just want to equalize your music, you can use the equalizer in your music app, although not all of them come with one. Even your car’s audio settings will have an EQ built-in more often than not, so if you don’t like the sound signature of your car speakers, you can play around with the EQ.

Fair warning: An equalizer can’t magically improve the quality of your headphones or speakers, but it can definitely help adjust the sound to make it more pleasant, according to your preferences. If you find your current audio setup sounds a bit harsh or dull, playing around with an equalizer is the first thing you should do, especially before you consider changing hardware.

How to use EQ

Before you get to work on an EQ, you should check what options you have. If you’re using Windows or macOS, you can use systemwide equalizers. Most Android phones will have a systemwide EQ in the settings, and on iOS and Android, you can use the equalizer in your preferred music app. Spotify, for example, has a nice equalizer built in, although some apps like YouTube Music on iOS don’t seem to have any equalizer options yet.

Here are the systemwide EQ apps we recommend:

For Android phones, the systemwide equalizer is typically baked into the settings app. iOS doesn’t have the option of a systemwide EQ yet.

However, many headphones come with companion apps which have equalizers in-built. If the companion app of your headphones has EQ, you can use it to tune the frequencies to your preference, which is especially helpful on iOS given the lack of systemwide EQ. Additionally, some headphone and earbuds like AirPods Pro (2nd generation) have dynamic EQ, or as Apple calls it, Adaptive EQ. This feature is automated, using digital processing to adapt the sound signature automatically, on the go, working with the audio source and the noise cancellation features.

Read more: Improve Your Spotify Audio Quality by Changing These Settings

Using EQ presets

Equalizers usually have presets which are templates with the appropriate settings for different kinds of audio. These presets have the different frequencies adjusted just right for specific music and audio types, like Rock, R&B, Electronic, Voice, and more.

So, if the many sliders of the EQ overwhelm you, you can use these presets. Typically, you would have to change the preset every time according to what kind of audio you’re listening to, especially if you’re using a systemwide EQ. For per-app EQ, you can leave the EQ on a single preset if you wish. For example, having your EQ set to the Rock preset in your music app is fine if you mostly listen to rock music.

Most equalizers will also let you adjust the sliders as per your preference and save them as new presets. For systemwide equalizers that you may want to set up and never touch again, this might be a good option.

Adjusting the EQ sliders

When it comes to actually configuring the EQ, you will have to play with the sliders to adjust them to your liking. EQs may have different numbers of sliders, i.e. frequency bands and bandwidth, depending on which EQ you’re using, but they’re almost always arranged in ascending order from left to right. This means that on the left, you will have the low frequencies, with mids in the middle and highs to the right.

The best way to adjust these sliders is to play the audio you would typically listen to, whether it’s a movie with dialogues and sound effects or a song you’re particularly familiar with, and move the sliders up and down, one at a time, until you’re happy with the way the audio sounds on your headphones.

Since different EQs have these sliders at different steps, you may have to do some trial and error before you figure out where each slider needs to be for your sound to be perfect for your ears. Increasing the intensity of a frequency by moving the slider up is called boosting while doing the opposite by sliding down is called cutting. To tune the sound to your liking, you’ll have to boost and cut frequencies according to your preferences.

Here are some quick tips for setting up each range of frequency:

Lows/Bass: Adjust the low-range sliders until the bass has a solid thump but isn’t overpowering to a point where there’s a distortion that causes a rattling sound or makes other sounds in the audio harder to hear. Bass should sound pleasant but without drawing out the other frequencies. If you listen to a lot of bass-boosted music, boosting it in the EQ will likely result in too much bass, so make sure to keep that in mind.

Mids: These frequencies can usually go unnoticed, but they’re crucial for voices, mostly male voices and some instruments. You will need to adjust the sliders for clarity and crispness, but be really careful not to go too high or too low with these sliders, since they can ruin the quality of your audio if you tune them too low or too high.

Highs/Treble: Treble is usually the most unpleasant, high-pitched sound when not in tune. Tune the high-range sliders to a point where they sound crisp, and don’t hurt your ears. It’s easy to cause ear fatigue with these frequencies, so make sure to set these sliders just right for the different kinds of audio you play. The key is to ensure nothing sounds too sharp or screechy.

There are also transitionary frequency ranges, which are on the edge of the aforementioned ranges, like lower midrange and upper midrange. Again the key to nailing these tunes is to play different kinds of sounds you’d usually play, and see how they sound as you adjust the sliders.

Should you use a parametric EQ?

Above, we’ve mostly referred to graphic EQ, which has sliders for different frequencies. The other kind of EQ is a parametric equalizer, which has the whole sound curve instead of being broken down into sliders for different ranges. The difference is that you get more granular control since you can move the smallest parts of the whole sound curve across the entire range of frequencies the human ear can hear.

You can individually adjust the frequency band, the center frequency, the gain, and the bandwidth. Adjusting a parametric EQ is more complicated as a result, but the overall philosophy remains the same — be careful, adjust the curve to ensure the lows, mids, and highs sound good to your ears, and test with different kinds of audio to ensure you’ve got the tuning right for your usage.

If you’re a novice, stick to a graphic EQ, but if you want to have a lot of control over how each specific frequency sounds, opt for a parametric EQ.

Getting the most out of your headphones

Using an EQ can be cumbersome, especially if you use a parametric EQ, but it’s a great way to adjust for the shortcomings of your headphones. However, if you’ve already used an EQ and the end result is less than satisfactory, you can opt for a digital-to-analog converter, a.k.a. a DAC.

Earlier, we discussed how sound works with vibrations and how sound files have these vibrations coded in them. Every audio playback device has a built-in DAC that converts the digital sound data into analog vibrations that need to be outputted for us to hear the sound. The sound file is made by first converting analog vibrations into a digital signal, so they must be converted back to audible.

Every audio playback device has a DAC, but getting a better DAC can help improve the quality of the sound you hear. I’ve been using a Fiio K9 Pro DAC along with my Sennheiser HD599 SE headphones, and it’s a great setup. If you’re sensitive to sound, getting a DAC is the next logical step. Your EQ adjustments will also be more noticeable with a good DAC sitting between your computer and your headphones.

The Fiio K9 Pro is still one of the higher-end DACs you can get, but there are DACs available at every price point if you want to enhance the sound on your headphones even further. You can also get smaller DACs for your phone, if that’s what you want.

Pro tip: Sound is subjective!

At the end of the day, keep in mind that sound is really, really subjective. What sounds good to you is a very personal thing, so even if I give you the exact sound curve or slider positions for my EQ, it’s likely that you won’t like it at all.

I use Both of us by B.o.B. ft. Taylor Swift as the benchmark song to judge a pair of headphones and my EQ settings since I think the song has a nice mix of frequencies. I cannot guarantee that you will agree with that choice, either.

As such, the best way to judge a pair of headphones or your EQ settings is similar to how we judge music. We may lay critique on it according to basic principles of what is supposed to sound good, but at the end of the day, what sounds good to you is what sounds good to you. So go on and play around with that EQ in-depth, and if you still don’t like the sound, consider getting yourself a new pair of headphones from our recommendations for the best over-ear headphones, or the best wireless headphones and earbuds, if that’s what you prefer.