How Noise-Canceling Headphones Work—and Why You’ll Never Go Back

Have you ever wondered about the magic behind noise-canceling headphones? It’s an amazing feature to have for headphones, shutting you out from outside noise that can be distracting. The truth is, I can’t ever go back to regular ones anymore.

The Audio Experience Is Much Better

It’s no secret that the audio experience is a lot better when wearing a pair of quality headphones, especially one that cancels out unwanted noise and sound. This can become particularly important in virtual work meetings or classes, and also when listening to music and gaming (go ahead and ask any gamer).

But have you ever wondered how noise-canceling headphones know what sounds to cancel out? I know I have. The secret lies in its tiny microphones built into its cups to pick up background sounds. It then creates an inverted sound wave (a sound wave opposite of another sound wave) to cancel these noises. There is also a difference between noise-canceling and noise-isolating when it comes to headphones.

Where Did It All Begin?

Before becoming a consumer electronics staple, noise-canceling headphones had their beginnings in aviation. In the 1950s, Dr. Lawrence Fogel did some work in the field of active noise-canceling. The purpose was to develop a system for canceling noises in airplane and helicopter cockpits for better communication.

The integration of such technology into electronic consumer products was conceptualized by Dr. Amar Bose, owner of the audio company Bose, as he was on a flight and was frustrated by the plane’s engine noise in 1978, a feeling I perfectly understand after a recent long-haul flight where I nearly resorted to stuffing napkins in my ears (yes, I did forget my headphones). However, the actual application to consumer electronics only happened in the subsequent decades that followed.

Introduced in 1989, the first commercially available noise-canceling headsets, the Bose Aviation, were then made available primarily for aviation workers. The popularity of noise-canceling headphones initially gained attention among professionals in the aviation field in the early 2000s, and general consumer demand followed suit as the increase in technological advancements grew. So, in the early stages, you couldn’t just go out and buy them, they were far too expensive. But as the technology matured and budget-friendly headphones with the same functionalities were produced by audio companies like Bose, Sony, and Sennheiser, these eventually became widely available.

Related

Noise Cancelling Headphones Make Gaming PC Noise Irrelevant

The sound of (algorithmic) silence.

The Magic of Noise-Canceling Headphones

Noise-canceling headphones block outside noise and let you hear your audio in peace. To do this, the headphones use active noise cancellation (ANC) that generates sound waves to cancel out incoming noise. One benefit of this feature is that you don’t need to increase the volume excessively, unlike standard headphones, improving your listening experience. Music is mostly unaffected by the ANC process (though this does depend on the quality of the headphones) and is played separately.

Related

What Is Active Noise Cancellation (ANC)?

This popular feature lets your headphones transport you to another world, but how does it actually work?

Tiny external microphones capture the ambient sounds that trigger a small amplifier to generate a sound wave that is in a different phase from the undesired sounds, therefore canceling them out. In earlier headphones, passive noise isolation offered some relief in blocking unwanted sounds, like the use of thick padding on headphone cups. But in-ear designs use deep insertion into the ear to block most external sounds. Although noise-canceling headphones seem pretty clever, they’re not perfect.

Noise-Canceling Headphones Aren’t Perfect—Yet

Noise-canceling headphones may be good at canceling low-frequency, steady sounds like the hum of an airplane’s engine, distant highway traffic, or air conditioning in an office due to the time needed for wave cancelation to work effectively. But less effective though when it comes to unpredictable and sudden sounds. This includes barking dogs, clicking on keyboards, or people talking next to you.

A wide variety of excellent headphones are available on the market right now. Some have Active Noise Cancelation technology built into them that reduces unwanted ambient sounds. However, a caveat is that this may not block all noise due to its inherent limitations depending on the headphones.

The reason why it’s harder for the ANC to tune out sudden, high-frequency sounds, is because these sounds are more rapid and unpredictable. This causes difficulty for the ANC system to generate the right sound waves to neutralize them in real-time, bypassing it.

Another thing to consider is the design itself. A lot of the headphones that have ANC technology feature the transparency mode, which intentionally allows certain external sounds to pass through. This helps in providing safety for users to remain aware of their surroundings when necessary. However, not all ANC headphones have this functionality, which tends to vary by manufacturer and model.

Adaptive ANC on the other hand, is a significant advancement beyond standard ANC. Since standard ANC struggles with sudden sounds, adaptive actually goes a step further by constantly monitoring and analyzing your surrounding sound environment and uses sophisticated algorithms, sometimes powered by AI, to categorize different sounds and detect sound changes. So it adapts in real time. If you invest in a good-quality pair of noise-canceling headphones that use adaptive ANC, this will be less of a problem for you.

Can Noise-Canceling Headphones Help Protect Your Hearing?

Most of us are aware that loud sounds can cause you to develop hearing loss over time. A lot of places in the world have become highly urbanized, and that comes with loud sounds (known as sound pollution), which can disturb not just your peace but potentially cause hearing problems (especially if you live near a construction site or attend too many rock concerts, for example).

Ear damage happens because of sound waves reverberating inside your ears. It’s a form of vibration that hits your eardrums, bones, and inner parts. Over long durations, this could be a serious risk. But as with other helpful applications, the technology used in noise-canceling headphones may alleviate the risk of long-term hearing loss (but should not be used as a replacement for actual hearing protection). This is possible through the active noise cancelation feature of your headphones. But that’s not all, wireless buds may one day give us all superhuman hearing.

Related

How Wireless Buds Might Give Us All Superhuman Hearing

We’ll make a supersonic man out of you.

What’s Next For Noise-Canceling Headphones?

Some of the noise-canceling headphones that you can buy on the market right now already use adaptive algorithms. These systems cancel out noises based on the surrounding environment. But what does the future hold for noise-canceling headphones? I believe more and more artificial intelligence will be used—and I’m all for it. The quality of the audio experience will probably get better.

Accuracy when it comes to the adjustment of surrounding sounds using AI will also continue to get better. There are circumstances where users need to hear their surroundings without taking off their headphones, and with AI, they may be able to more intelligently adjust to amplify or prioritize certain sounds over others.

With advanced features using AI in the future, personalized audio experiences in the future may also become a thing by analyzing your hearing profile and adjusting the sound settings automatically for more personalized and optimal listening. This technology will likely consider factors like ear shape, listening habits, and hearing sensitivity, to suit your individual auditory preference.

Personally, I can’t go back to standard headphones after trying out a good pair of quality noise-canceling ones, and it will likely stay that way. I’m excited about the possibility of more AI being used in this space, and when newer products roll out, I’ll be first in line to try them out. If you don’t want to pay for another pair of headphones, you can always make your headphones sound better for free.