How to Equalize: A Beginner’s Guide to Setting and Adjusting an Equalizer

With an audio equalizer (EQ), you can tweak the sound of your headphones to exactly what you want.

In this article, you will learn:

• How to make EQ adjustments for your headphones from scratch
• How to use frequency response measurements
• And what to do if they don’t come with an equalizer inside a companion app

Understanding EQ Settings

• By using frequency bands, Q values, and filters, you can precisely manipulate the sound of your headphones.

Audio equalizer, or EQ, is a tool that helps you tweak your headphones to sound better to your ears. EQ settings are essentially filters that isolate frequencies into individual frequency bands and let you manipulate their intensity.

EQs typically consist of multiple frequency bands from only 2 (bass, treble) to 31 or more.

Example of a 3-band equalizer (on the right):

Example of a 31-band equalizer:

Difference between analog and digital equalization

Analog equalizers work by changing the electrical flow that goes through passive electronic components like capacitors.

The main problem with analog EQs is that they aren’t as precise as digital ones.

In contrast, digital equalizers order a DSP (digital signal processing chip) to change the audio data, which a DAC (digital to analog converter) later interprets as a boost or cut. More on that later.

With digital equalizers, you can be much more precise about how you want your adjustment to be. However, some digital EQs don’t work well with DSPs, resulting in quieter sound and crushed dynamics.

How to EQ

• EQ involves boosting or cutting problematic frequencies or frequency groups. Some of the most important ones are listed below.

You perform an EQ by either boosting or cutting frequencies. Boosting is when you increase the loudness of a specific frequency, and cutting is when you decrease it.

• Boosting is required when you feel a specific frequency region, like bass, lacks loudness. Doing that increases the signal amplitude, so the amp sends more power to boost the bass.
• Cutting is needed when you hear that a particular frequency region is masking the other regions or is uncomfortably loud and harsh. For example, if you find vocals overly sibilant, try cutting between 5kHz-8kHz for female and 3kHz-6kHz for male singers.

To make your EQ-ing process easier, it’s good to know which frequencies contribute to specific sounds. To name just a few:

• Bass rumble: 20Hz-50Hz
• Bass punch: 60Hz-120Hz
• Warmth and fullness: 120Hz-250Hz
• Vocals: Females: (main 350Hz-3.000Hz, harmonics 3.000Hz to 17.000Hz); (males: main 100Hz-900Hz, harmonics 900Hz-8.000Hz), higher frequencies add clarity
• Guitars: Main 80Hz to 1.200Hz, harmonics and sparkle from 1.200Hz-12.000Hz
• Cymbals: Main 300Hz-600Hz, shimmer 600Hz-6.000Hz, air and presence 6.000Hz-20.000Hz

As you can see, every element in music needs a wider frequency spectrum to sound as natural as possible, so tuning your headphones correctly is very important.

You can look at our in-depth frequency response article to learn more about what musical instruments and sounds lay in different frequency regions.

How to fix boomy, muddy bass?

If your headphones have a bass that’s so strong it distorts and masks sound in the midrange, by making it less detailed or quieter, you have boomy bass.

However, bass-heavy tuning is sometimes difficult to recognize by ears, especially if you’re used to it.

To know if your headphones have muddy bass, try lowering frequencies below 250Hz and observe if you can hear instruments and vocals better.

• Try to find a comfortable spot between letting the midrange frequencies “breathe” a little and still have enough bass to satisfy your taste.

How to fix extreme treble?

Extreme treble is easier to recognize as its harshness often results in physical ear pain. Typically, it manifests in sibilant vocals, harsh electric guitars, or overly sizzling cymbals.

• Try lowering frequencies above 4.000Hz or 5.000Hz and observe if that helped relax the sound. If it did and you like the result, you can leave it like that. Or you can do some fine-tuning and more accurately determine what frequencies are problematic and only cut those.

How to Correctly Use Equalizer

• You can equalize the sound by ears or by using a frequency response graph (it’s much simpler).

Remembering the frequency range for basic sounds is easy, but correcting the sound of your headphones just by using your ears isn’t. It takes a lot of experience to do that.

Furthermore, due to the physiology of our head, pinna, and ear canal, not everybody hears the same. Moreover, each person has their favorite tuning that differs from the neutral flat response.

So how to start equalizing your headphones? There are 2 ways how to do that.

Equalize them by ears

When you don’t have objective frequency response measurements, you must rely on your ears to do the job. That can be hard, especially if you don’t have reference headphones to base the tuning on.

So, try to use a specific song you know the most, and you heard it with headphones, in a car, restaurant, at a party, concert, etc. That way, you at least have some idea of what tuning you want to achieve.

1. The best way to start EQ-ing by ear is with the bass. Lower it and observe if that makes the mid-range sounds clearer and the bass punch tighter. Remember that bass lies between 20Hz-250Hz, so if you have multiple bands in this region, cut all of them a little.
2. After achieving a tighter bass, proceed to the midrange (250Hz-4.000Hz). First, lower each frequency band and see how it changes the sound. If it becomes too quiet or less dynamic, boost it up and drop it slowly until it sounds right.
3. Then, move to the high frequencies (4.000Hz-20.000Hz). Repeat the same procedure as with midrange; first, start cutting the frequencies and boosting them back up and vice versa. Jump between different frequency bands and tweak them slowly until they sound right to you.
4. Lastly, start fine-tuning across all frequencies. Make small changes to see how your headphones react. Bring up the bass a bit to see if that makes the sound fuller.

Equalize by using frequency response measurement

Frequency response measurement shows how your headphones produce specific frequency regions within an audible spectrum.

Understanding the measurement also tells you how that response deviates from the target response (Harman, free-field, diffuse-field, etc.).

Finding a frequency response measurement for the headphones you’re trying to tune will tremendously speed up your tuning process since you can see precisely which are the “bad” frequencies.

This is how you start equalizing your headphones:

1. Find a frequency response measurement for your headphones or make one if you have the necessary equipment. The key is to understand what the measurement shows you. Some represent a neutral target as a flat horizontal line (like ours), whereas others opt for a more curved target line (which follows an equal loudness curve).

2. Observe where the measurement deviates from the target and try to correct them within the EQ. Always listen to music that you know, so you know how it should sound while performing tweaks.

3. Knowing that the measurements above 5kHz are less accurate, use a mixture of the measurement data and your taste to find appropriate treble tuning.

Cutting frequency ranges is better than boosting

Cutting frequency ranges is better than boosting because you avoid audio distortion or clipping. 

Importing a song into Audacity reveals that waveform peaks are already very close to the threshold limit. By boosting, you might push those peaks over the line, which can lead to audible distortion.

• You should avoid over-clipping to avoid poor audio quality and damaging your equipment. That’s why cutting is a preferred way of equalizing audio gear.

This advice is primarily for those who boost all frequency bands, thinking that they have improved sound, but in reality, they have only boosted the loudness. Learn how to boost bass without distortion.

On the other hand, if you must significantly cut one and boost the other frequency, try using audio equalizers with a pre-amp feature. More on that later.

How to listen and adjust for specific frequencies

• Use a song you’re familiar with before starting to EQ your headphones.
• Use the knowledge about where specific instrument frequencies are located.

With some practice, you will start detecting deviations in the frequency response without looking at measurements.

Types of Equalizers

There are multiple types of audio equalizers, from analog EQs that use knobs to digital ones that use graphic user interfaces. Since most analog ones only use “bass” and “treble”, we’ll focus on more precise digital ones.

Digital equalizers come in 3-band and up to 10-band versions (or even more). They can be:

• Basic EQ with only +/- dB controls

• Parametric EQ ones with Q factors, pre-amps, and filters

What are Q values?

Using more a professional EQ lets you adjust the “Q” value, which is how many neighboring frequencies near the main one you want to boost. That way, you control how wide of a peak or dip you want to make.

Using the Q value gives you better control over how you want to EQ your headphones. Let’s take a look at some examples where Q value might come in handy.

1. We used different Q values when adjusting frequencies to flatten the response more accurately.

2. Here’s the comparison between the original (blue) response and the one adjusted by using different Q values (red).

One example of a more in-depth equalizer comes with Edifier headphones. It offers a “Q factor”, and you can manually select a frequency band. But you’re limited to only 4 bands, all below 10kHz.

To get a better EQ experience on your smartphone, you should use apps like Wavelet or Flat Equalizer. However, desktop PC apps like APO Equalizer (with Peace UI) will grant you the most in-depth control.

Why should you use a pre-amp when boosting?

You should use the pre-amp to avoid potential distortion.

If your audio equalizer has the feature (or any kind of loudness limiter or control), adjust it by lowering the loudness as much as you boosted the highest frequency band.

• For example, if you boosted 8kHz for 6dB, reduce the volume on your pre-amp by -6dB.

How to use filters?

EQ filters help you select how much of the spectrum you want to change at a specific frequency. It works in conjunction with the Q value to give you even greater control over the sound.

Here’s a table of the most useful filters:

There are other filters as well, but they aren’t that useful for equalizing headphones.

Equalizing Headphones

In most cases, headphones don’t faithfully reproduce audio.

• The reason is that different tunings can elevate specific music genres.
• Also, every person has a tuning preference, so manufacturers want to cover as many different tastes as possible. However, they don’t always match yours. 
• To make matters worse, people hear some frequencies differently, and our ear canals have different resonant frequencies.

As you can see, there are numerous reasons you should be equalizing your headphones.

How to EQ headphones for different types of audio

Headphones arrive with various tunings that can make a specific frequency range shine more than the other. However, sometimes their default tuning doesn’t align with the type of audio you want to listen to.

Here’s how to EQ headphones to benefit a particular music genre or improve a user experience.

How to EQ for clear phone calls

To equalize headphones for clear phone calls:

• Prioritize human voice frequencies between 300Hz and 5kHz.

There are other harmonics below and above, but those are insignificant for audibility. Therefore, if you use your headphones primarily for answering calls, boost that area to hear callers clearer.

How to EQ for sound clarity

When trying to EQ for sound clarity:

• It is best to focus on treble frequencies, especially above 8kHz and near 16kHz, which gives you a bit more air.

Remember to be gentle when boosting frequencies between 8kHz and 14kHz, as they quickly lead to harshness and shimmer.

How to EQ for sound quality

If you wish to EQ for sound quality, you must aim for a neutral sound signature. The reason is that neutral tuning is the least stressful for the drivers, so they can truly show what they’re capable of.

You can use the techniques mentioned above to achieve a neutral frequency response.

How to EQ for audiobooks/podcasts

The best equalizer settings for audiobooks or podcasts are:

1. Reduce bass frequencies below 250Hz to avoid muddy male vocals.
2. If you find female vocals harsh or sibilant, lower the 5kHz to 8kHz region (3kHz to 6kHz for male speakers).

How to EQ for games

To amplify effects in video games:

1. Add more bass and sub-bass frequencies (below 125Hz) for boosting effects.
2. Also, boost the 300Hz to 5kHz region to increase the legibility of the dialog.

How to Use Equalizer on iPhone & Android Phones

Many Bluetooth headphones nowadays come with companion apps, which have their own customizable EQ. If not, using a third-party equalizer is a viable alternative.

Here are the mobile EQ apps that we recommend:

Android phones

Android phones can choose from many third-party EQ apps inside the Google Play store (you can even install apps without using the official store). We mostly recommend these two apps:

• Wavelet: It offers 9-band EQ (+/-10dB), Auto EQ (pre-saved EQ for various headphone models), gain limiter, and manual sampling rates that help avoid distortion.

• Flat Equalizer: It offers 10-band EQ (+/-15dB), Bass Boost, Loudness Boost, and Virtualizer for surround sound effects.

iPhone (Apple) phones

Unfortunately, if you own an iPhone (or any other Apple gadget), you don’t have many EQ options. Your only choice are the ones integrated into the apps.

There are no noteworthy third-party EQ apps in the App Store, and iOS also doesn’t allow software installation outside Apple’s official marketplace.

Here’s how you access EQ presets in the Apple Music app:

1. Go to “Settings” and find “Music”.

2. Then, go to “EQ” and select which EQ preset provides the best sound.

How to Use Equalizer on Spotify

Music streaming app Spotify has a built-in equalizer with 6 frequency bands with +/-6dB boost or cut. This is how you access it:

1. Open the app and the settings by clicking on the gear-looking icon in the upper-right corner.
2. In Settings, click on “Playback”.

3. Scroll down and click on the “Equalizer”.
4. Enable the equalizer and start adjusting.

As you can see from the pictures, Spotify’s EQ is quite limiting. It works best for adjusting bass and lower midrange but jumps from 2.4kHz to 15kHz in higher frequencies.

If Spotify’s custom EQ doesn’t solve your issues with the sound, try switching between different EQ presets below the EQ (although EQ presets rarely offer a good sound).

To make more precise adjustments, you’ll have to use some of the third-party apps mentioned above.

Frequently Asked Questions (FAQ)

Conclusion

This was a tutorial on how to EQ headphones using 2 different approaches.

• The one with measurement is more straightforward, as you already know what frequencies need correction.
• On the flip side, tuning solely by your ears takes some time and lots of jumping back and forth. But gives you a custom sound.

Remember that almost all headphones can benefit from EQ. We all hear slightly differently, so your friend’s perfect headphones might sound off to you.

Therefore, we encourage you to experiment a little and try to achieve the sound you genuinely like. The worst it can happen is that you return to default tuning.