Most folks are at least vaguely familiar with what an equalizer (EQ) looks like. For some of us, those rows of sliders arranged into a kind of smiley face are an icon of the ’80s – remember the one Tom Cruise was forbidden to touch by his stoic dad in Risky Business? Or how about that ridiculous system Ferris Bueller had in his bedroom?
An EQ can help you dial in the sound that suits you best.
Unfortunately, understanding how an EQ works and using it properly is a much more elusive concept. You don’t want to pull a Tom Cruise and just shove every slider to the max – that’s going to sound terrible.
EQs put the power of sound sculpting at your finger tips. And you know what they say: With great power comes great responsibility. OK, so an EQ isn’t an actual superpower, but it can get you closer to the sound you’re looking to get out of your gear … if you know what you’re doing. With that in mind, here’s our top-to-bottom guide on using an EQ.
Why do I want to use an EQ?
Electronics manufacturers have their own ideas about what a piece of gear should sound like, but EQ lets you have your say. Also, we don’t always get to listen to music in ideal environments. Many of us listen while commuting or exercising, where ambient noise can have a nasty effect on how our music sounds. An EQ can help.
Maybe you have a pretty bass-heavy pair of headphones that you need to tone down a bit. Or perhaps you listen to a lot of EDM, but the treble is too sharp and needs to be pulled back. Whether you’re looking for more punch, a warmer sound, or bass that will rattle your innards, an EQ can help you dial in the sound that suits you best.
What does an equalizer do?
At its most basic, an EQ manipulates frequencies. The technology first took off as a piece of analog electronics, initially used in recording studios before making its way into the home. Whether analog or digital, an EQ is used to adjust different elements of sound to achieve an end result that appeals to the listener.
The first thing you want to try … is to decrease the level of a frequency, rather than increase.
The graphic EQ – which is what we’re going to focus on here – looks like a graph (no kidding!) with frequencies on one axis and decibels (dB) on the other. From left to right you’ll find “sliders” that allow you to adjust certain frequency bands up or down along the dB scale. Bass frequencies start on the left, with midrange frequencies in the middle and treble on the far right.
If you’ve already got a firm grasp on what frequencies and db are, then feel free to skip ahead to the ‘Playing with your EQ’ section. If not, the following little snippet of Acoustics 101 will probably come in handy.
All sounds – everything you hear – are essentially vibrations, which we can visualize as waves moving up and down at different speeds, or frequencies. The faster the wave moves, the higher the pitch. For example: bass frequencies — such as those you hear in a hip-hop groove — move very slowly, while higher pitches (treble), like the chime of a triangle, move very quickly.
Every pitch a music instrument plays has a core frequency measured in hertz (Hz), which is like a speedometer reading for the waveform. Hertz measures how many times (the frequency) a wave completes an up and down cycle in 1 second. If the wave moves up and down 50 times in a second, that’s expressed as 50Hz. At the theoretical limit, a human can only hear from 20Hz to 20kHz (20,000 cycles). But in reality, most humans’ hearing tops out around 15kHz or 16kHz – the older you are, the less treble you can hear.
Since all of the sound you’ll ever hear lives in this 20Hz-20kHz zone, those are the numbers that will border your typical EQ. And moreover, most of the pitches your ears really focus on live between 60Hz and 4kHz – that’s the meat of the music. A piano’s highest note, for instance, lives at 4,186 Hz (4.2kHz). There are also sounds called overtones, and an EQ will affect them, too. These sounds, which primarily live in the 10kHz – 14kHz neighborhood aren’t something that your ears naturally latch onto, but they have an effect on the sound as a whole, so it’s important to keep that in mind when messing around with that section of the treble band.
The decibel is a unit of measurement used to express volume levels or loudness. When you move a slider up or down on an EQ, you are increasing or decreasing the loudness of that particular frequency. It’s important to know that small db adjustments can have a big effect on the sound, so tread lightly. It’s wise to start with a 1 dB change and move up or down from there. Since decibels use a logarithmic scale, a 5-10 dB change represents a dramatic increase or decrease to a particular frequency band.
Playing with your EQ
Finally, the fun part! Now that you’ve got a grip on what your EQ does, it’s time to start playing around with making adjustments. Go ahead and start playing some music that you are really familiar with, pull up your EQ, and move some sliders up or down to hear in action what you’ve been reading about. You’ll find out soon that small adjustments can have a pretty wild effect on how things sound. Here’s some direction on how to approach things:
Your own auditory input is what makes this process all the more personal and enjoyable.
You may notice that it will take a moment after making an adjustment to hear the result. This is normal. It’s also normal that you may have to boost the overall volume after reducing any frequencies. For instance, if you want more bass and treble in general, you can pull down some of the midrange sliders. Then, boost the volume up a bit and see what you think of the result. Not exactly right? Then it’s time to get more targeted with your adjustments, and for that, you’ll need to know what each frequency sounds like. We’ve got a guide for you at the end of this article that spell things out pretty nicely.
What about EQ presets?
EQ presets like “Rock” and “Jazz” are a quick-and-dirty way to get to a different kind of sound without a ton of effort. While these probably won’t give you the exact sound you’re looking for, they can be handy for getting you started. You might want to start with a preset, then customize it until it is just right. Some EQs, such as the one built into iTunes, will actually show you what the curve looks like when you select a preset. This can help you understand what different EQ settings can do for you.
Parametric EQs are tricky, involved, and not for the faint of heart or inexperienced user. We suggest getting a grip on a graphic EQ first. Once you’re more intimately familiar with what frequency manipulation does, you can dive into this much more advanced flavor of equalization.
Targeting your efforts
As promised, we’ve provided a breakdown of the frequency spectrum to help you get your head around which sounds live where. If you’re ever stumped, this guide can help you drill down to the offending (or lean) frequency and make a more effective adjustment. Below are guidelines, not steadfast rules, and your own auditory input is what makes this process all the more personal and enjoyable. And that’s really the point: Have fun!
Sub bass – 20Hz-60Hz
While humans can technically hear down to this region, it’s less cerebral and more gut. Somewhere down here is where your subwoofer will make that eerie sound of deep space in sci-fi movies, and this region can add some serious, unearthly power. However, you would very rarely want to add more of this sound, and taking away from here can help give the music more overall clarity.
Bass – 60-200Hz
The majority of the time, a stalwart hip-hop groove will start at or around 60Hz. The foundational, big-hitting lower register rests in this domain, including the heavy punch of the kick drum, and even lower tom drums and bass guitar. Moving up towards the 200Hz line begins to affect the very lowest boom of acoustic guitars, piano, lower brass and strings. If the music is too darned heavy, or not heavy enough down low, a bit of an adjustment here will help.
Upper bass to lower midrange – 200Hz-800Hz
Rising above 200Hz starts to deal with the lighter side of the low end. This region is where the meatier body of an instrument hangs out. Adding EQ around the middle of this spectrum can add a bit of oomph to richer tones, including the lower end of vocals, deeper notes from synthesizers, low brass and piano, and some of the golden tones from the bottom of an acoustic guitar. Lowering the level a bit here can clear up some space, and open up the sound. Moving to the 800Hz region, you’ll start to affect the body of instruments, lending more weight with addition, or lightening the load with subtraction.
Midrange – 800Hz-2kHz
This area is a touchy one, and can change the sound quickly. Putting on the brakes in this region can take away the brittle sound of instruments. Adding some juice can give things a metallic touch, and can wear down your ear quickly if pushed.
Upper mids – 2kHz-4kHz
Adding EQ around the middle of the 200Hz-800Hz spectrum can add a bit of oomph to richer tones, including the lower end of vocals.
Presence/sibilance register – 4kHz-7kHz
This is commonly referred to as the presence zone, and leads into the highest range of pitches produced by most natural instruments. Boosting the lower end of this scale can make the music sound more forward, as if pushed a little closer to your ears. Backing it off can open the sound, and push instruments away for more depth. The top end of this region is also responsible for the sharp hissing “s” of vocals, known as sibilance. If sharp consonants are popping out at you like the bite of a snake, cutting a few dB from around 5-7kHz can solve the issue, and save you some pain and suffering.
Brilliance/sparkle register 7Hz-12kHz
Raising or decreasing the level at the lower end of this register can help bring some vibrance and clarity, adding a tighter attack and a more pure sound. If things are a little too sharp, or causing some pain after listening for too long, lowering the bottom end of this register can help out quite a bit. Towards the top is where things start to space out into less tangible definition, moving away from what you can hear more towards what you can feel. That shimmering resonance at the tip of a cymbal crash floats around in the regions of this space.
Open air – 12kHz -16kHz
Once you get up here, things really become more subjective. The bottom registers continue to affect the higher overtones of instrumentation, and synth effects from electronic music can pop around in that region as well. Moving further up, it becomes more about creating a spacier, open sound. However, there are very few points in which you’d want to affect the sound much around 14kHz or above — many older listeners won’t be able to even hear these sounds. If you want to boost a bit of space in the belfries of the music, you can add some level here. Too much, however, will make things start to sound synthetic.