Guide to Noise Canceling Headphones
Noise-canceling headphones are making waves (literally!) lately. These headphones promise to cut out sounds from low-flying airplanes to background chatter on the bus or in the office, giving people the chance to turn down the noise in their environments so they can focus on the task at hand.
Active noise-canceling headphones can not only reduce outer sounds to allow you to better enjoy your music or podcasts. Still, they can even be turned to ‘silent mode’ so you can enjoy some peace and quiet even when the children are screaming for your attention.
Cutting Out the Noise
Okay, so noise-canceling headphones might not completely block out every sound around you. But they do offer a generous muting capability. Over-ear noise-canceling headphones are particularly good at this, thanks to their thicker design ‘muffling’ outside interferences.
This isn’t just pleasant, but can actually have beneficial effects on our health and wellbeing. Researchers discovered a relationship between excessive noise exposure and an increased risk of heart attacks and stroke. Not to mention the strain it can have on our mental health, causing problems with sleep and concentration.
Considering a refrigerator emits sounds of around 40 dB, and an open-plan office can be as loud as 60 dB, it’s concerning to discover that damaging effects to our physical and mental health can start at just 65 dB. So, noise-canceling headphones don’t only offer sanctuary but can actually protect us!
Airlines to Urban
Although over-ear noise-canceling headphones are excellent gifts for audiophiles, the technology wasn’t initially designed for the urban lifestyle. In fact, noise-canceling tech was first designed to improve the comfort of airline pilots on long flights.
The effective sound reduction is perfect for protecting pilots’ ears when exposed to continuous loud noises such as airplane engines. When coming into a more commercial setting, they were initially marketed and sold to passengers on long flights for the same reason.
These days, however, noise-canceling headphones offer a refuge in modern urban living. Quietening the sounds of other commuters, the roar of traffic, or the babble of your co-workers, these gifts for audiophiles are a godsend in almost any setting.
How Do They Work?
Although it might feel like some sort of magic fuelling your noise-canceling headphones, we can assure you it’s real technology!
What is Sound?
To understand how noise-canceling headphones work, you must first understand a bit about sound.
We’re sure you remember from high-school that sound operates a bit like a wave, with the thing emitting the noise sending vibrations that are picked up by your inner ear and transformed into noise that you can understand.
While this isn’t a full description of how sound works, it’s a useful way to think of it for our purposes.
Noise-canceling headphones work by mirroring the soundwave heading towards you by using a physics trick known as “anti-phrase” or “destructive interference.”
The mirrored sound needs to be the same frequency as the noise it intends to cancel but will be the opposite amplitude.
To picture this more easily, think of the jump rope games you played as a child. If two people hold each end of the rope and one person moves one end, it will cause a ripple. But if both perform the same disturbance, the waves will cancel each other out. This is the basic principle behind “destructive interference.”
But how does this work in practice?
Well, actively noise-canceling headphones are equipped with tiny microphones on the earpieces that listen to ambient noise. They register the soundwaves and electronically create identical but inverted noise that cancels out any incoming sounds.
This new noise is played through your headphones’ regular speakers to quieten your environment without affecting anyone else in the room.
Although, in theory, noise-canceling headphones could cancel out all sounds, in practice, they only work particularly well with consistent noises like engines.
This is simply due to timing. Naturally, a low, consistent sound will be more straightforward for the microphones to register and deal with than the sudden noise of a dog barking or someone trying to get your attention.
However, this can be a blessing to some people; for example, if you want to cancel out background chatter but still want to hear your barista when making your morning coffee order.
Active vs. Passive
Pretty much any type of headphone can provide passive noise reduction capabilities by ‘muffling’ the sounds around you. This works thanks to the headphones being made from noise-reducing materials such as high-density foam. This can make them heavier than standard headphones but provide a sound reduction of around 15-20 dB!
Active noise-canceling headphones are the ones that utilize modern technology to create a more effective sound reduction and sound-canceling waves. By erasing incoming soundwaves, active noise cancellation can offer a reduction of an additional 20dBs, allowing up to 70% reduction in the sounds you hear!