If you’ve ever had to listen to the sound of a plane turbine for 8 hours or tried to make an urgent deadline while your co-workers are busy discussing Bird Box, you’ve probably wished that the world around you had a mute button.
While they’re not a perfect mute button, noise-cancelling headphones can drastically lower the noise around you -- in some cases by as much as 80 decibels.
They work using a concept known as destructive interference to effectively remove outside sounds from what you want to hear.
If you’ve ever wondered how these headphones work -- and if they’re worth buying -- this guide has you covered.
Noise Cancelling vs Noise Isolation? What’s the Difference
This guide is going to focus primarily on noise cancelling headphones.
So, before we get started, it’s important to understand the difference between these noise cancelling and noise isolating headphones.
Noise isolating -- or passive noise cancelling -- headphones work by blocking outside noises. Kind of like if you cupped your hands over your ears.
This is often done using thick ear cups or snug-fitting earbud tips to keep sound waves around you from reaching your ear drum.
Most noise isolating headphones top out around 20 decibels of background noise reduction.
If you’re looking for an excellent pair of noise isolating headphones consider these:
If you need more reduction, you’ll need to check out noise cancelling headphones.
Noise cancelling -- or active noise cancelling -- headphones are very different from noise isolating headphones. They essentially use technology to eliminate the ambient noises surrounding you.
If you’re listening to music or watching a video, you’ll be able to hear better. But most models will also allow you to put the headphones on with no input at all and simply enjoy a bit of peace and quiet.
They are capable of reducing overall noise by as much as 80 decibels depending on the model.
So How Do Noise Cancelling Headphones Work?
Noise cancelling headphones use digital signal processing (DSP) to work their magic.
There’s a microphone -- or microphones -- embedded in the headphones . They’re often in the ear cups for over- or on-ear models and in-line for earbuds or in-ear models. So if you’re worried about appearance, they don’t stick out like a mic on gaming or bluetooth headsets.
This mic records the ambient noise around you and sends it to the DSP chip. The chip then creates a signal that is audibly opposite to the noise around you.
When it’s played back to your ear with the audio from your phone, tablet, or whatever you’re listening to, the result is a dramatic reduction in outside noise.
This is known as destructive interference. While that might sound frightening, it’s perfectly safe for your ears. But it can slightly reduce audio quality -- even on the best noise cancelling headphones.
For cheap models, it might not just degrade quality, it could even introduce additional noise to your audio stream. So definitely read reviews to get an idea of how any headphones you are considering will perform.
Do Noise Cancelling Headphones Actually Work Though?
Yes they do. But it’s important to set expectations.
Active noise cancelling headphones aren’t magic noise eliminating machines… but they can definitely help in the right situation.
Because of the science behind destructive interference, it tends to filter out bass-heavy, steady noises best -- such as train or plane noises.
Most decent noise cancelling headphones can also handle lower volume conversations and similar background noise, but you won’t find a pair of noise-cancelling headphones that perfectly remove loud conversations, TV dialogue, or music from your surroundings.
Noise cancelling headphones also do not hand handle loud, sudden sounds well. So doors slamming or kids yelling will still come through in your audio feed.
So, in most cases, you actually want a pair of headphones with both passive and active noise cancelling abilities.
What slips past the DSP will hopefully end up muffed, if not eliminated, by the design of the headphones itself.
Common Questions
While there are plenty of bad options out there, the exact one that will be the best for you depends on a range of factors that we can’t account for.
In general, in-ear and over-ear models will provide the greatest level of noise cancellation due to the combination of passive and active cancelling effects.
Both the Sony WH-1000XM3 and Bose QuietComfort 35 II receive outstanding reviews from online experts.
But everything from ear shape and how you hear things to where you plan to use your headphones and how much cancelling you want will ultimately impact which model is best for you.
If you can, find a local retailer that sells noise cancelling headphones and will let you demo them. This will offer a level of comparison that no online review or website can match.
You don’t need to be listening to music or watching a video to take advantage of noise cancelling benefits.
In fact, since active noise cancelling is handled by hardware in the headphones, you don’t even need to plug most headphone models in to use noise cancelling. Just slip them on, active noise cancelling, and enjoy a much quieter environment.
This type of use is for sleeping in noisy apartments or just removing the constant din of busy office space.
Because active noise cancelling changes the sound coming from your device, you’ll likely notice some differences in audio quality.
However, as long as you get a good pair of headphones, the listening experience will remain rich. It’s just not going to be an audiophile-grade experience.
Still, if you’re trying to listen to music on a plane with your favorite cans, the experience is already less than ideal anyhow.
So it’s a trade-off you’ll need to decide for yourself. But in most cases, we find that if you need noise cancelling, the impact on audio quality is far less than the benefits of removing outside noise.
The answer here is complicated -- and partly a matter of preference.
Over-ear headphones often provide better sound quality and improved comfort for long listening sessions.
But they’re bulky and less-than-ideal for active use -- such as at the gym or on your morning jog.
In-ear models are much more portable, but you’ll rarely get the rich bass and wider sound stage you’d enjoy with a pair of over-ear headphones.
However, they’ll slip into your gym bag or pocket with no problems and won’t stand out if you’re wearing them in public.
In the end, the best design for your needs is really up to what you prefer and where you plan to use your headphones.
In most cases, it’s all about comfort and convenience.
If you’ve never owned a pair of wireless headphones, the ability to move around without worrying about cords is pretty awesome.
Not to mention, there’s less clutter and one less cable to keep track of.
But going wireless also means dealing with battery life. And noise cancelling headphones require more power than standard wireless to work their magic.
Still, most high-end options account for this with high-capacity batteries to help you listen longer.
If you plan to listen all day long, wired is probably better. But for a work shift or a flight, the battery in a pair of wireless noise cancelling headphones likely has you covered.
If you’re using your noise cancelling headphones in the office or on the go, most offer buttons to enable or disable the feature.
This means you’re not stuck removing your headphones every 5 minutes but can still get things done or navigate the world around you safely.
Some high-end options even include gestures or other features for quick disabling. For example, you can cup your hand over the earcups on Sony’s WH-1000XM3 headphones to temporarily disable noise cancelling. The mic will even still route through outside audio to help you hear.
Features like these make your experience much more enjoyable and are often worth the added expense of higher-end models.
While most of the popular models are larger, around-ear models, there are noise cancelling headphones in a range of shapes and sizes.
Plantronics, TaoTronics, and Bose all make excellent in-ear noise cancelling headphones in both wired and wireless designs if you’re looking for something more discrete or for use on the go.
Summary
As long as you don’t expect total silence, noise cancelling headphones can offer some much needed quiet in today’s busy world.
Noise isolating headphones don’t offer the same level of noise reduction but are substantially cheaper.
However, if there’s room in your budget, a good pair of over-ear active noise cancelling headphones are a great way to eliminate office noise, the endless hum of plane engines, air conditioners, and other common distractions and allow you to rest better or focus on what you’re listening to.
In-ear active noise cancelling headphones are better suited for on-the-go use or when you prefer a less obvious option for listening.
Regardless of your pick, be sure to check headphone reviews and -- if you can -- try a few pairs at a local retailer. This will ensure your choice is a good fit for your ears and hearing.
Disclosure: You should know that in some cases, we may receive a referral fee (at no additional cost to you) for products purchased through the links on our site. These links help support our work but they do not influence our content. Our editorial recommendations are always genuine and we try to feature only the best products and services. Why trust us?
[1] Forbes : Are Noise Cancelling Headphones Worth It?
[2] How Stuff Works : How Noise-Canceling Headphones Work
[3] Sound Guys : How Do Noise-Cancelling Headphones Work?
[4] Audio Technica : How Do Active Noise-Cancelling Headphones Work?
[5] Mental Floss : How Do Noise-Canceling Headphones Work?
[6] Cnet :How Do Noise-Cancelling Headphones Work?
[7] Scientific American : How do Active Noise Canceling Headphones Work?
[8]Wikipedia : Active Noise Control