How Soundwaves and Headphones Work

soundwaves and headphones

Soundwaves and Headphones Work Together

What are Soundwaves?

Soundwaves and headphones are inextricably linked.  A sound wave is a disturbance of particles over a medium (air, bone, water, etc.) that travels away from the source in a wave-like form. It’s a pressure wave.  Imagine the ocean waves traveling from the source of disturbance all the way to the shore. Particles of water disturb the water next to them, and the energy is transferred over the medium.

When it comes to sound, the source of disturbance can be a person’s vocal cords. They disturb the air around them and through repeat air particle disturbance your eardrums pick up the vibration, this is when you hear the person’s voice.  The vibration of air travels in all direction from the source and loses some of its power over distance. So, over distances, the voice volume is lower than at its source.

How fast can sound travel over the air?

Sound travels at the speed of 343 meters per second (m/s) over the air and even faster over liquids (water) and solid matter (like bone or metal). This is also how the best bone conduction headphones work.

Can you block sound waves?

Surfaces that are soft like cloth, curtains, and foam absorb the sound and reflect very little of it. This makes them great for sound isolation as they create a “sound-blocking” effect.  Minimal sound deflection is the reason why foam is used as a sound-absorbing material to create excellent acoustics.

A hard surface like a concrete floor, on the other hand, deflects most of the sound waves and thus creates an echo effect.  You can best detect traveling sound in big cities where the sound waves are deflected from building walls.

How Do Soundwaves Interact with the Human Ear?

When an air vibration reaches your ears, it makes your eardrums vibrate.  From the eardrums, the vibration travels through the middle ear to the Cochlea.  The vibration is then transferred into an electrical signal that your brain can process and understand (hear).

This is a simple explanation. The whole process is a bit more complicated. The stronger the vibration, the higher the volume of the sound.

What is the Frequency we Hear Every Second?

How many sound waves hit the human ear per second is measured by frequency. Its unit for measuring is hertz (Hz), defined as one cycle per second. More sound waves/cycles hitting the ear increase the measured frequency.

Normal hearing for humans is considered 20 – 20.000 Hz / sound waves per second.  A low number of sound cycles is heard like almost a perfect silence with only a couple of tones. And, 20.000 Hz sounds are complex and often indescribable, like city noise.

Most sounds we hear are somewhere in between but still 1000s of Hz.  Keep in mind that human hearing diminished over time, so it’s important to avoid damaging situations with noise-cancelling technology.

What is Noise Cancelling Technology?

Noise-cancelling technology is a process that uses microphones to sense the noise coming from your surroundings, and then creates sound waves that are 180 degrees out of phase with the incoming sound. The new sound waves are sent back to your ears, which cuts down on the level of ambient noise you hear, so you can focus more on what’s being said or listened to.

There are a few different ways that noise-cancelling technology can work. The most common way that it works is by using microphones to sense the ambient noise around you. Once it has sensed the noise, it creates sound waves that are 180 degrees out of phase with the incoming sound. These new sound waves are then sent back to your ears, which will help to cut down on the level of ambient noise you hear.

Another way that noise-cancelling technology can work is by using a physical barrier to block out the sound. This type of noise-cancelling technology uses materials like foam or rubber to help reduce the amount of ambient noise that is heard.

How Does Noise Cancelling Work?

Imagine a world without the sound of engines, traffic or other people. What would you hear? A presence that can’t be ignored is something we all strive for in our lives- but it doesn’t have to make us unhappy!

Headphones help cancel ambient noise by using “phase inverter” technology which creates anti-noise (the opposite way around). It sounds complicated at first, but once mastered this skill becomes second nature and does wonders with focusing on tasks like working out, coding, or studying for an exam.

When waves are out of phase, they cancel each other. For example, if I delay one wave by exactly half a wavelength so that both the peak and trough match up with their corresponding neighbors on an identical standing side-by-side like in this picture below then no matter how much louder or quieter my original sound was; it won’t make any difference because those two vibrations will always just blend into nothing.

What are the benefits of noise-cancelling technology?

There are a few different benefits that come with using noise-cancelling technology. The first benefit is that it can help you to focus more on your audio experience. When you are not distracted by ambient noise, you can better focus on what’s being said or listened to

Another benefit of noise-cancelling technology is that it can help you to relax. When you’re surrounded by loud noises, it can be difficult to relax and unwind. Using noise-cancelling technology can help you to tune out these loud noises and relax in peace.

Are there any types of headphones that use noise-cancelling technology

There are several different kinds of headphones that make use of noise-cancelling technology. The most common type is over the ear headphones, which typically have cushy pads inside them that act as a barrier between you and outside noise. Another popular kind of headphone with this functionality are in-ear headphones, which tend to carry the same benefits as in-ear headphones but often offer additional benefits of noise blocking.

What about wireless Bluetooth Noise Cancelling in-Ear Headphones?

Nowadays you see more and more people using wireless Bluetooth noise cancelling in-ear headsets. They are becoming more popular because of the freedom they offer. The Bluetooth allows you to connect your earphones to your smartphone or other devices without the hassle of wires getting in the way. You can use them for calling, listening to music or simply just being able to hear what’s going on around you without taking off your headphones when someone is talking to you.

Why would you need noise-cancelling headphones?

Noise-cancelling headphones offer several different kinds of benefits. The first benefit is that they can help you to focus more on your audio experience. When you’re not distracted by ambient background noise, you can better tune into the sounds coming through your speakers. Another benefit is that they can help block out loud noises, which can be great if you want to relax and unwind at the end of a busy day. And finally, noise-cancelling headphones can be versatile because there are many different kinds to choose from–you can find them in all sorts of styles including over the ear, in-ear and Bluetooth options.

Types of Noise Cancelling Headphones

There are many different types of noise-cancelling headphones to choose from, depending on your specific needs. Over the ear headphones with noise-cancelling technology typically come with cushy pads that act as a barrier between you and outside noise. These headphones will help to offer better focus when it comes to your audio experience. In-ear headphones with noise-cancelling technology can be a great option for those who want to block out ambient noises that may be going on in their surroundings.

Wireless Bluetooth noise cancelling in-ear headsets can also be a good option because they allow you to connect your earphones wirelessly without having the hassle of wires getting in the way. They make for an especially popular choice among those who use their headphones primarily for calling or listening to music.

The leading brands in noise cancellation are Apple with their Airpod range and Bose with their Quiet Comfort range. There are some cheaper options on the market that work well, but typically you pay for what you get when it comes to noise cancellation technology. How much you’re prepared to spend will usually determine how good the quality of your sound is.

Over the Ear Noise Canceling Headphones

These are large headphones that sit over your ears, perfect for blocking out noise at home or work. Some of them even have a built-in microphone that allows you to make hands-free calls, adding convenience to these already popular headphones.

In-Ear Noise Canceling Headphones

These are small earphones that fit directly into your ears and let in little external noise. They come with different-sized rubber tips so that they can be fitted snugly into your ears–this is important for achieving the best noise-cancelling effect.

Wireless Noise Canceling Headphones

These are headphones that don’t require any cords to connect them to your audio device. This can be a great option if you want added mobility when you’re listening to music or making calls. The downside is that they typically cost more than traditional headphones.

Bluetooth Noise Canceling Headphones

These are headphones that use Bluetooth technology to connect wirelessly to your audio device. This is a convenient option if you don’t want any wires getting in the way while you’re using your headphones

Difference Between PNC and ANC

Passive noise cancellation (PNC) is a type of noise reduction that is achieved when the headphone pads seal off the ear canal from the environment. This blocks out most external noise, but it can also make your music sound muffled

Active noise cancellation is a type of noise reduction that is achieved when tiny microphones inside the headphones detect external noise. These microphones create sound waves that are 180 degrees out of phase with the incoming sound. The new sound waves are sent back to your ears which cuts down on the level of ambient noise you hear so you can focus more on what’s being said or listened to.

What is “Passive Noise Cancelling”?

The correct term for passive noise cancelling is passive noise isolation since actual cancelling is only happening in the active-named process.  Nonetheless, you can understand it as passive noise cancelling or isolating, most people will still understand you.

Passive sound isolation works with the help of physics. Since sound travels over the air, if you cut direct air connection of the headphone drivers (source of music) with the outside world, leaked noise will be decreased.

By keeping the sound waves inside the headphone casing by blocking them physically, you make it difficult for people not wearing the headphones to hear the music.  Some music still leaks, but it’s greatly diminished. The best noise isolating headphones are always closed-back with a tight fit.

Why Might Someone Prefer Passive to Active Noise Cancelling?

Passive noise canceling (noise isolating) headphones are usually much cheaper because they don’t include ANC circuitry which costs additional money. The exceptions are the best budget noise cancelling headphones that do not require batteries which can be a hassle to charge up, limits usage time, and has a limited expected life.  Additionally, great PNC headphones do not substantially alter sound quality which is often the case with active noise-cancelling headphones due to how the technology works

What is Active Noise Cancelling?

Active noise cancelling is a process that includes microphones picking up ambient noise. Then the headphones send the ambient sound to ANC circuitry that transfers it to the “noise-reducing” signal, which is then sent to the headphone drivers. When both, the ambient noise and its opposite noise-reducing counterpart reach your ears, they cancel each other out.

It’s a process predominantly used in headphones that results in a dramatic reduction of background noise, which is helpful in many situations and especially during travel and work. Since sound waves follow a particular pattern if you create an opposite pattern and combine them together, they create silence.

Why Might Someone Prefer Active to Passive Noise Cancelling?

There is only one major advantage of active noise-cancelling headphones over their passive alternatives.  ANC headphones are much more effective at removing unwanted noise from your perception.  But put on a pair of headphones with active noise canceling, and suddenly you’re in a much calmer environment, it makes it easier to cope with the stress of flying and many frequent travelers swear by them.

On the flip side, the ANC technology is complicated, needs energy, costs more money to manufacture, and is overall more of a hassle to use. But for many people, the benefit of the improved removal of noises around you makes it worth it.