Each day, we’re surrounded by sound, whether the hum of a fridge, the buzz of a phone vibrating, the roar of traffic in the distance, or the melody of a song on the radio. Sound comes at us constantly, and we often don’t think twice about it.

However, when most people stop to think about sound, they immediately think about how loud or soft it is. This is called amplitude , and it represents the height (or volume) of the sound waves. That’s one part of the equation, but there’s another side to sound we often don’t consider: frequency.

Think about the low rumble of a distant thunderstorm vs. the sharp, high-pitched beep of an alarm clock. These sounds feel very different, don’t they? It’s not just the volume that changes; it’s the frequency or number of vibrations per second that gives each sound its unique character.

So, if you’ve ever wondered why certain sounds are easier to listen to while others make your ears ring, I'll break down the difference between high vs. low-frequency sounds for you.

What Is Sound Frequency?

Sound frequency refers to the number of vibrations or cycles a sound wave makes per second.

Imagine it like the rhythm of a wave in the ocean or how quickly it moves up and down. This speed, or frequency, determines how high or low the sound will be, which we experience as pitch.

So, every time you speak, sing, or even hum, you're creating sounds at different sound frequencies, often without even realizing it.

If you’re speaking in a higher pitch, like when you imitate a high voice, that’s a higher frequency. In contrast, when you speak in a deep, low, NPR-style tone, you're hitting lower frequencies. In fact, you probably move through a whole range of frequencies just by having a normal conversation.

To understand this better, let’s look at some examples: A dog’s whistle might be at a very high frequency, way beyond what humans can hear, while the growl of a lion sits on the lower end of the frequency spectrum. The hum of your refrigerator? It’s a low-frequency sound. Your phone’s ringtone, on the other hand, might hit a higher frequency.

Sound frequencies are measured in hertz (Hz) , or cycles per second. One hertz means the sound wave makes one full vibration in one second. So when you hear a sound at 100 Hz, that means the sound wave is vibrating 100 times every second. The low fundamental frequency of a bass guitar might fall around 40 Hz, while a bright bell tone could be as high as 4,000 Hz (4kHz) or more.

The lower the frequency, the lower the pitch, and the fewer cycles per second.

Humans can hear frequencies between 20 Hz and 20,000 Hz . This is our audible range. Sounds below 20 Hz are called infrasound . Think of the low rumbles of thunder or earthquakes. On the flip side, sounds above 20,000 Hz are ultrasound , like the high-pitched beeps from certain medical devices or some dog whistles.

For most of our daily experiences, the sounds we hear fall within the mid-frequency range, which is usually between 300 Hz and 3,000 Hz . This range is where the majority of human speech happens and where most instruments and sounds that we perceive most clearly are situated. When we move outside of that, we get into either the high or low-frequency extremes, which we experience differently.

Understanding High-Frequency Sound

To explain high-frequency sound, I want to start by stepping into the world of ultrasound. Again, these are sound waves that vibrate at frequencies higher than 20,000 Hz (or 20 kHz). You’ve probably heard the term “ultrasound” before, usually in the context of medical imaging, where doctors use it to get a peek inside the body.

However, ultrasound isn’t some modern invention. These sound waves have been around as long as sound itself.

In fact, animals have been using ultrasound long before humans even figured out how to make use of it. For example, bats and dolphins are masters of echolocation. They emit high-frequency sound waves to navigate and hunt.

Dolphins send out clicks and listen to the echoes bouncing back, allowing them to locate prey or even communicate with one another.

Though we’re not aware of them, these higher frequencies can still influence the way we feel or respond to certain situations, whether through the vibrations they create or their use of technologies that shape our world.

Understanding Low-Frequency Sound

Low-frequency sounds, especially those below 20 Hz, are referred to as ultra-low frequencies or infrasound. These sounds are so deep and slow that we can’t hear them, but they’re still very much a part of our world.

Some natural events, like volcanic eruptions or the movement of ocean waves, generate these ultra-low frequencies. Even some large, fast-moving animals, like elephants, use infrasound to communicate over long distances. These sound waves travel through the earth and air for miles, making them perfect for sending signals through vast spaces.

We humans have also found ways to harness ultra-low-frequency sounds too. Large machinery, like engines and turbines, often produces low-frequency vibrations that we usually feel more than hear.

In the music world, infrasound can be used deliberately to create a deep rumble from a subwoofer at a concert. While you might not hear the sound directly, your body senses it.

Dealing with High and Low-Frequency Sound in a Studio Environment

Now, before we get too deep into the science of it all, let's get down to what really matters for you as a musician or producer: how these high and low frequencies affect your studio setup. After all, we’re here to make music, right?

In the studio, we deal with sound from both ends of the frequency spectrum. The question is: how do you handle all this range, and how should you think about it?

First, let’s talk about the low end .

In most setups, regular studio monitors are designed to cover a decent amount of the low-frequency spectrum. These monitors typically can handle frequencies down to around 40 Hz or so. But when you really want to dig deep into the 20 Hz to 40 Hz sub-bass territory, you’ll want a subwoofer .

A subwoofer’s job is to reproduce these ultra-low frequencies that regular monitors can’t quite reach, giving you the full spectrum of sound, especially if you’re mixing genres like EDM, hip hop, or film scores.

With that said, not every producer needs a subwoofer. If your monitors can handle the lows decently and you’re not working on sub-bass-heavy tracks, you might not need the extra oomph. Just make sure your monitors have good, clear, low-end response, and you’ll be fine for most projects.

On the other end of the spectrum, we have high frequencies. Tweeters are responsible for handling the higher frequencies, usually from about 2,000 Hz up to 20,000 Hz (or even beyond, in some cases). These are the frequencies that add clarity, presence, and detail to your mix. This is where you'll hear the sharp top-end of a snare drum, the shimmer of cymbals, or the sparkle of a vocal.

How to Treat Your Studio for High and Low Frequencies

Now that we’ve got a solid grasp on how high and low frequencies work, let’s talk about how to treat your studio with them in mind. As I've said in several articles in the past, if your studio isn’t properly treated, even the best equipment won’t give you the sound you’re after.

We know that sound waves sound differently depending on their frequency, but they also act differently. High-frequency sounds have shorter wavelengths, meaning they don’t travel as easily through materials.

Instead, they tend to reflect off hard surfaces, such as walls, windows, and metal. If you've ever heard that annoying slap-back echo when you're recording in an untreated room, that's your high frequencies doing their thing.

On the flip side, low and mid-range frequencies have much longer wavelengths. These lower sounds have a bit more "mass" and can pass through materials more easily. They also tend to accumulate in corners or areas where the sound waves meet at certain angles. This is why you might notice that your bass-heavy tracks sound muddy or undefined in untreated spaces.

So, the question becomes, how do we treat these different types of frequencies individually?

Acoustic Treatment and Soundproofing for Low Frequencies

Since low frequencies, with their long wavelengths, can easily travel through hard surfaces, we have  to take special considerations when trying to deal with them.

Bass traps are the first and most effective piece of the acoustic treatment puzzle.

These are designed specifically to deal with low frequencies, which, as I mentioned earlier, tend to collect in corners. They work by absorbing the excess low-end energy and reducing unwanted resonances.

The most effective bass traps are made of dense, absorbent materials like fiberglass or rockwool, which have a high sound absorption coefficient at lower frequencies. This means they’re great at soaking up deeper bass tones.

In addition to bass traps, you can also use low-frequency absorbing panels , particularly on the walls. These panels are often made of thicker foam or dense fibrous material. They help absorb low-mid frequencies (which range roughly from 100 to 300 Hz) and further clean up your room’s overall acoustics.

Now, if you live in an apartment or in close quarters with neighbors, you'll want to make sure those low-frequency sounds don't leak into the next rooms over. Low-frequency sound waves travel far, and your bass-heavy mixes may easily be a nuisance to those living or working around you.

To soundproof your studio for low frequencies, focus on isolating your room from the external environment. Adding mass to your walls, floor, and ceiling using mass-loaded vinyl (MLV) or double-layered drywall is a good start.

If you're really looking to take it up a notch, you can decouple your room's structure using resilient channels or isolation clips. These systems essentially create a “gap” between the walls and ceiling, preventing vibrations from traveling through the materials.

For the floor, consider using rubber isolation pads or floating floors to absorb the impact of low-frequency vibrations.

Acoustic Treatment for High-Frequency Sound

While very low-frequency sounds might be the trickier challenge, high-frequency sounds have their own set of problems in the studio environment.

Unlike low frequencies, high-frequency sounds have much shorter wavelengths, and as a result, they’re more prone to reflection. This means that without proper treatment, your studio could quickly become a mess of unwanted echoes.

To control high-frequency sounds, you’ll need materials that can absorb or diffuse the sound before it has a chance to reflect back at you. Acoustic foam is a common choice. You'll want to strategically place foam panels on the first reflection points, where sound from your monitors first hits and then bounces back at you. Typically, this includes the walls to the left and right of your speakers, as well as the ceiling directly above.

Another option is to use fabric-wrapped fiberglass panels . These are great because they can handle a wider frequency range, not just high frequencies, and are often more effective than foam when it comes to smoothing out the acoustics in a room.

For windows, you can use heavy curtains that are thick and heavy enough to absorb high-frequency reflections from glass.

Final Thoughts

While the human ear spends most of its time perceiving sound in the mid-frequency range, low and high-frequency sounds are very important for us to have a grasp on as producers and engineers. Even though it's difficult not to think of ultra-highs and lows as seemingly imaginary sounds, since they aren't a part of our human hearing, we now know that they have a significant impact on the way things feel , and that's an important concept to take with you.