Does your new pair of noise-canceling headphones put a painful feeling of “pressure” on your ears? It turns out that your mind is playing tricks on you.
Over the last decade, noise-canceling headphones have become more common, more affordable, and more effective. But as headphones become better at filtering out external sounds, more and more people complain that they cause ear pain, headaches, and a feeling of inner-ear “pressure.” These complaints date back further than 2009, so why hasn’t this issue been resolved yet? Well, first, we have to understand how noise-canceling headphones work.
ANC Headphones Listen to External Noises and Cancel Them Out
Contrary to popular belief, active noise canceling (or ANC) headphones don’t block out noise by physically shielding your ear from external sound waves. They aren’t like fluffy shooter’s earmuffs; they’re just small pieces of plastic. So how do ANC headphones cancel out sound?
Like light, sound travels through the air in “waves.” And just as different frequencies of light are recognized as different colors, different frequencies of sound are perceived as different pitches.
The thing is, sound is a “pressure wave.” Unlike light, sound is capable of moving through solid objects, like walls, water, and a plastic pair of headphones. Low-frequency sound waves are especially good at moving through solid objects (think of a bass drum), but high-frequency sounds (like the nasty sound of a CRT TV) aren’t that great at moving through objects.
So, ANC headphones aim to eliminate low-frequency sounds. They do this by monitoring your noise environment with a built-in microphone, identifying the frequencies of said noises, and blasting your ears with an anti-noise wave that cancels out the unwanted external sounds.
This sounds complicated, but it’s easy to understand. An anti-noise wave is basically a mirror version of the sound that your headphones are trying to eliminate. It’s the same frequency (pitch) of the unwanted noise, but with a reversed polarity (again, a mirror version). When two sounds with opposite polarities meet one another, they’re both canceled out. It’s weird, but that’s science.
Why Do My Ears Feel “Pressure” On an Airplane?
Okay, so ANC headphones cancel noise by pumping an anti-noise wave into your ears. But why do they hurt people’s ears and cause headaches?
Most people describe the feeling of ANC headphones as a sort of “pressure” on the ears, like the changes in atmospheric pressure from ascending in an airplane or diving deep into the ocean. So, it’s important to understand how air pressure works (and its relationship with sound perception) before we try to figure out why ANC headphones put “pressure” on your ears.
