HomeBuyer's GuideHow Do Noise Cancelling Headphones Work Physics?

How Do Noise Cancelling Headphones Work Physics?

If you love to listen to music while traveling, a good pair of headphones can be the best companion for your travel period.

However, the background noise can spoil your relaxing moments. Indeed you do not want to spoil your pleasant moments due to the surrounding noise.

That’s why you need a noise cancelling headphone.

In fact, many travelers use to prefer noise canceling headphones for the same reason.

You might hear about these headphones but not have a clear idea about them. Then you can go through this write-up.

Today I am going to let you know about how do noise-canceling headphones work physics.

At first, I would like to give an idea about noise-canceling headphones.

What Is Noise Cancelling Headphone?

Noise cancelling headphones are those headphones that can reduce unwanted ambient sounds using the active noise control. This sound cancelling makes it possible to listen to audio without increasing the volume.

These headphones can prevent us from background noise if we want to avoid the surrounding noise.

It will also be helpful if you want to sleep in a noisy vehicle such as Airplane. They can also help you in a busy train station or just at home if you are looking for some peace.

Aren’t you curious to know who invented these surprising headphones?

Don’t worry. I am here to remove all your curiosity.

Who Invented Noise Cancelling Headphones?

In the 1950s, Dr. Lowrence Jerome Fogel designed one of the first noise cancelling headphones systems. Jerome submitted patents about active noise cancellation, specifically in the field of aviation.

He created this system to reduce noise for the pilots in the cockpit area to make their communication easier and protect hearing.

But later on, Willard Meekes designed an active noise control model. He has applied it to circumaural earmuffs for advanced hearing protection.

Finally, in 1978 a sound engineer and the founder of Bose Corporation Dr. Amar Bose thought of reducing noise in the headphones.

He thought this when he was on a flight to Europe. On that flight, he could not listen to music & relax because of the airplane engine noise. Then he decided on the concept of building noise cancelling headphones.

When his trip was over, he started to research noise reduction technology.

So finally, Dr. Amar Bose invented this noise cancelling headphones.

Types Of Noise Canceling Headphone

There are two types of noise canceling headphones: Active and passive.

Technically speaking, any headphone can provide some passive noise isolation. The reason is, the materials of the headphones themselves block out some sound waves of higher frequencies.

However, the best passive noise-canceling headphones are circum-aural types that are specially constructed to increase noise-filtering properties. They are filled with layers of high-density foam or other sound insulation materials.

However, these passive models have some severe limitations. That’s where active noise-canceling headphone comes in.

Active noise cancelling headphone can do everything that passive one can do. Its structure makes a barricade that blocks the high frequency sound waves. They also add an extra level of reduction by erasing low frequency sound waves.

Doesn’t it sound interesting?

Maybe you already have realized that there is an exciting physics working behind these high-tech devices.

Right now, I am going to explain that. Stay with me to know the details.

How Do Noise Cancelling Headphones Work?

They actually create their own sound waves just like the incoming noise in every aspect except for one. The sound waves of headphones are 180 degrees out of phase with the intrusive waves.

Look at the image below. It will be clearer to you.

Notice the two waves — the one is coming from the noise-canceling headphone and the other one is associated with the ambient noise. They have the same amplitude and frequency. And their crests and depression are arranged in such a way that the crests of one wave line up with the depression of the other wave and vice versa. As a result, the two waves cancel each other out, creating silence. This phenomenon is called destructive interference.

So, what do you think about the ultimate result?

The listener can concentrate on the sounds that he desires to hear.

Of course, several components are needed to acomplish this effect. They are:


A microphone is placed inside the ear cups to listen to external sounds that cannot be blocked passively.

Noise-Canceling Circuit

Electronics are also placed in the ear cups to sense the input from the microphone and generate a print of the noise, not the frequency and amplitude of the external sound waves. Then they produce a new wave that is 180 degrees out of phase with the associated noise waves.


The anti-sound formed by the noise-canceling circuit flows into the headphone speakers along with the audio. The anti-sound removes the noise by destructive interference but does not interfere with the desired sound waves in the normal audio.


The term active refers that energy need to be supplied to the system to generate the noise canceling effect. A rechargeable battery is the source of that energy.

Using these components, noise-canceling headphones can reduce the noise up to 20 dB. That means about 70% of the ambient noise is effectively blocked.

So, that was the working procedure of noise cancelling headphones.

Now you will get to know some benefits of using noise cancelling headphones. look here.

Benefits Of Noise Cancelling Headphones

These headphones are beneficial in many ways, as mentioned below:

Peaceful Traveling And Commuting

I have said earlier that noise-canceling headphones are greatly appreciated among travelers and commuters.

They are ideal for airline and train travel, as they can reduce unwanted background noise like the hum of airplanes and bus, train engines. Therefore, the outside noise won’t disturb you if you want to read, sleep, study, or listening to music while traveling.

Protect Your Hearing

Noise Cancelling Headphones offer great hearing protection against the constant level of noise.

The amazing thing about them is that much of the external sound is blocked. Therefore, you don’t need to increase the volume of your music to avoid the outside noise.

Instead, you can keep the volume at a moderate level. It helps you to preserve your ear health.

Keep You Focused On Any Works

It helps you to focus on several tasks more comfortably.

This sound cancelling headset allows you to talk over the phone without any hassle. You can also focus on your studies or office work as the external sounds will not distract you.

So you can enjoy your everyday routines without any disturbances of unwanted sound.

Sleeping Aid

Noise cancelling headphones are also known as sleeping aid. It can prevent you from car honking and snoring that can affect your sleep.

Both passive and active noise-canceling headphones can help you with it. So it is convenientfor people who are suffering from insomnia or other sleeping disorder.

Everything has some negative facts besides the positive sides. These noise cancelling headphones are not an exception to this.

Now, let’s know about the downsides of these headphones.

Downside Of Noise Cancelling Headphones

Here are some downsides of noise cancelling headphones.


These headphones have more complex technology. That’s why they are costlier than regular standard headphones due to their additional manufacturing cost.

No Situational Awareness

The biggest downside of noise cancelling headphone is it keeps you unaware of your surroundings. So it will be dangerous if you use it on the road or while driving. You won’t hear any horns or traffic signals that can lead to any accidental happenings.

So these are the downsides you can face with a noise cancelling headphones.

Anyway, most people have a big question regarding these headphones whether they can cancel noise without music or not!

If you are also interested in having the answer, the following section is for you.

Do Noise Cancelling Headphones Cancel Noise Without Music?

Yes, they can do it. As these headphones are designed for canceling outside noise, they can do it without any music too.

Recently, I was on a flight. Then I was wearing my noise cancelling headphone without playing music throughout the whole flight. I enjoyed a peaceful flight without hearing any outside noise.

Hence, I must say noise cancelling headphones can cancel noise without music.

No more today. Let’s conclude it here.


Finally, you have got to know the details about how noise cancellilng headphones work physics? I tried to explain the theory that is working behind the noise cancellation. Their flipsides and downsides are also included here.

So, I hope the whole concept is clear to you now.

Thanks for reading this article.

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