Science & Technology

How Do Noise Canceling Headphones Actually Work?

The world is getting louder, and not in a good, front-row-of-a-Foo-Fighters-concert way. Increased congestion in cities means cars are honking more frequently; increased construction rates have led to what feels like a 24/7 onslaught of building noise; and it feels as though every time you board a plane, the baby-screaming has been elevated to new heights.

It should come as no surprise that the demand for noise-canceling headphones has skyrocketed in recent years. The very thought of hopping on a plane, train, or automobile with a regular pair of headphones that mercilessly allow outside noise to ruin your music (or nap) is enough to make any experienced traveler cringe.

What Actually Are Noise-Canceling Headphones?

There seems to be widespread confusion regarding noise-canceling headphones. Some people think they simply reduce ambient noise through extra layers of padding, or an exceptionally airtight design. But that only refers to noise-isolating headphones, not noise-canceling headphones.

Noise isolation (sometimes referred to misleadingly as "passive" noise cancellation) works by isolating your ears from as much ambient noise as possible, usually by ensuring a super-tight seal around your outer ear, or by utilizing dense, sound-deflecting materials. It's that simple. And while this can have a noticeable and positive impact on your listening experience, it's no match for true noise-cancellation technology (sometimes referred to as "active" noise cancellation), which actively blocks incoming and unwanted sound waves from your environment.

So how exactly do noise-canceling headphones actually work?

First, Microphones Are Needed

Although it may seem a bit strange to imagine tiny microphones doing work outside of your headphones, they're the key to the whole process. These microphones take in the ambient noise around you and immediately process the noise as a distinct sound wave, which is then passed along to the inner circuitry of the headphones.

Now, For The Attack

Here's where the term "active" noise cancellation comes into play. Once your headphones receive the processed sound wave delivered by the external microphones, they go to work creating a sound that is the exact opposite of the incoming wave, which cancels it out. This happens thanks to physical properties that any surfer will likely be familiar with: If you take any two identical waves and place them directly on top of one another (so that their highest and lowest points are "in phase"), they combine to form an even larger wave.

If, on the other hand, you align the two waves so that the highest points of one line up with the lowest points of the other (so that they are "out of phase"), the two waves cancel each other out, and you're left with nothing.

Noise-cancelling headphones actively eliminate ambient noise by giving unwanted sound waves a taste of their own sonic medicine.

Of course, it would be impossible to make this process 100 percent effective outside of a lab, but some noise-canceling headphones have come startlingly close to achieving noise-canceling perfection.

Oh, They Have Have They?

These Paww WaveSound 3 Noise-Canceling Bluetooth Headphones, for example, manage to deliver top-notch sound while eliminating an incredible amount of ambient noise through active cancellation. Combining a state-of-the-art CSR chipset with multiple microphones, the WaveSound 3's block out as much as 20dB of unwanted ambient noise, independent of ANC function — making them an especially great option for air travel. And they're super comfortable to boot.

These headphones are easily foldable into the included case for increased durability, and a built-in microphone lets you make or receive calls when connected to your phone.

Armed with this new knowledge, we hope that the next time someone tries to sell you on some run-of-the-mill noise-isolation headphones, you'll politely turn them down and opt for a far superior set of noise-cancelling headphones, such as these Paww WaveSound 3 Noise-Canceling Bluetooth Headphones, which are on sale for over 45% off at just $79.99.

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Written By
Curiosity Staff
October 11, 2017