These speakers sound as good as they look.
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ZDNET’s key takeaways
- Equalizers let you fine-tune specific frequencies to balance sound.
- They help fix issues with your speakers or room acoustics.
- You can easily boost clear tones while cutting out noise.
I remember it like it was yesterday: sitting in my car, cranking up Van Halen’s 5150, and spending the entire album fiddling with the 10-band EQ I’d installed to get the best sound possible.
You don’t see a lot of physical equalizers these days, which is sad because they were always so cool to have. Instead, most everything is software-driven now. And that’s fine. It may not be “audiophile-level fine,” but at least it’s something.
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For those who didn’t spend their youth trying to tweak every knob and button on a stereo rack to get the best sound possible from their speakers, you might be wondering, “What is this EQ of which he speaks?”
Let me explain.
What’s the frequency…
One way sound is measured is in terms of periodic vibrations, measured in hertz (Hz), which is the property of sound that determines pitch. Humans have a finite range of frequencies they can hear, specifically, 20 to 20,000 Hz. Those frequencies are broken into octaves which are:
- 16 – 32 Hz – the lowest notes humans can hear.
- 32 – 512 – the frequencies of rhythm (lower and upper bass notes)
- 512 – 2,048 – the range where the human voice is located
- 2,048 – 8,192 – the range where labial and fricative sounds are
- 8,192 – 16,384 – the range of brilliance, bells, cymbals, and sibilance
- 16,384 – 32,786 – nebulous sounds passing the upper range of human hearing
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How does that work out in a way that’s better understandable? To break frequency down into the simplest terms, you have:
- Lows – the first two entries in the list above
- Mids – the third and fourth entries in the list above
- Highs – the final three entries in the list above
An equalizer allows you to raise or lower the levels of specific frequencies, and different EQs offer different amounts of adjustment. For example, you might get some cheaper earbuds with an included app that offers a custom EQ option, but the EQ is limited to three bands.
Usually, three-band EQs allow for adjustments of lows, mids, and highs. The problem with three-band EQ is that you have zero precise control. In other words, if you raise the “lows” in a three-band EQ, you’re raising everything from 16 – 512 Hz. What is that a problem?
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Say you want more kick drum in the mix. If you bump the lows up in a three-band EQ, you’re not only boosting the lowest frequencies but also the higher end of the low range, so the sound can get a bit muddy.
Bump that three-band EQ to a five-band EQ and you get a bit more control. A typical five-band EQ might let you raise specific frequencies, such as 60 Hz, 230 Hz, 910 Hz, 3,600 Hz, and 14,000 Hz. Now you can bump up 60 Hz and get a bit more kick drum in your mix. At the same time, you can lower 910 Hz to reduce that tinny sound (too much midrange makes it sound very tinny).
A ten-band EQ might be broken down into:
- 31.25Hz
- 62.5Hz
- 125Hz
- 250Hz
- 500Hz
- 1kHz
- 2kHz
- 4kHz
- 8kHz
- 16kHz
Note: kHz is kiloherz
Now, we’re talking.
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I’ve used 32-band equalizers, and you can imagine how much time I’ve spent tweaking those. In larger EQs, sound is typically broken down into low, low/mid, high/mid, and high. Every EQ is different, but they all do the same thing… raise or lower specific frequencies to change the overall sound produced by a device.
Why use an EQ?
Let’s say you just purchased a pair of earbuds, and out of the box, they sound cheap. Usually, cheap headphones and earbuds share similar sonic palettes – little bass, overamped mids, and dull highs. You’ve heard them before; everyone has.
That’s where EQ can come in handy. Many Bluetooth earbuds suggest downloading and installing the accompanying app, which often includes an EQ. Install the app, connect it with your earbuds, and make the following adjustments:
- Increase the lows
- Decrease the mids
- Increase the highs
Make it a nice sloping curve down to the mids and a rising curve to the highs. Now play your favorite song and see how those inexpensive earbuds sound. Vast improvement, right?
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You might also find the app has a few presets to choose from, often organized by music genre. As you might expect, the sound of different musical genres improves when certain frequencies are adjusted. For example, if metal is your jam, you’ll want to boost lows and highs, but be careful not to bump up mid/lows; otherwise, the sound will get muddy.
If you listen to a lot of podcasts, you’ll want to boost the mids, because the human voice is front and center. Classical music tends to benefit from a fairly flat EQ when listened to through headphones or earbuds, but can really come alive with some added bass and highs when listening through speakers.
EQ is a personal matter
The thing about EQ is that it’s very personal. You can talk to 100 sound nerds or audiophiles and hear 100 different opinions. The most important thing for you is to find the EQ curve that best suits your needs.
And because everyone’s hearing is slightly different (for example, I’ve lost about 50% of the hearing in my right ear, so I have trouble hearing highs unless they’re bumped a bit more than usual). I know exactly how to set an EQ to perfectly fit my taste.
It’s not just about your hearing either. You also have to take into account your equipment, the room you are listening in, ambient noise, etc. All of those things play into how you’ll adjust the equalization to get the most out of what you’re listening to.
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And if you have an attached subwoofer, you’re talking about yet another layer of consideration (do you let the crossover only send the lowest frequencies to the sub, or do you give it a bit more?).
After using EQ long enough, you’ll develop the same understanding and can quickly adjust the EQ sliders (physical or digital) to achieve the best sound possible.
Any chance I can get to improve the sound I hear, I’ll take it. If that means using an EQ, I’ll do it… and happily so. The only word of warning I’ll give you is that EQ is a deep rabbit hole to dive into. At the same time, it’s a very rewarding chase for perfection.