When I bite my nails while wearing sound cancelling earbuds, I can hear a moment of static as my skull absorbs the sound or whatever. What's going on here?
from zaphodb2002@sh.itjust.works to nostupidquestions@lemmy.world on 04 Sep 05:08
https://sh.itjust.works/post/24675647
from zaphodb2002@sh.itjust.works to nostupidquestions@lemmy.world on 04 Sep 05:08
https://sh.itjust.works/post/24675647
I assume it has something to do with the sound cancelling. It uses white noise or something, right? I’m running out of nails to test this.
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Think of noise as a sine wave on a Cartesian plane (the X-y graph you used in math class). The noise goes up and down so that y=1 at the max and y=-1 at the minimum.
What happens if we add 1 when y=-1? Well, now it’s 0. And what happens if we add -1 when y=1? It’s 0 again. That’s basically what noise cancelling does. It adds the “opposite” to make the sound equal 0. That’s super layman’s terms, but I hope it makes sense. It’s basically trying to make the opposite of whatever it hears.
But when something is physically touching your body, your ears can’t absorb that “opposite” sound because the original sound is kind of already absorbed in your body, if that makes sense?
I assume you meant “What happens if we add 1 when y=-1?”
Yup, thanks. Fixed
Don’t know…but maybe don’t bite your nails. Just in general.
Oh wow, what helpful advice. Please dispense more wisdom, oh mystical sage!
Or maybe actually don’t. Just in general.
True, but not an answer to their question.
I will not accept any answer that doesn't begin with "Think of noise as a sine wave on a Cartesian plane...."
The noise cancelling headphones are listening to noise coming from the outside and cancels them out. When the source of the sound is in your mouth (see also: bone conduction), the headphones can’t hear or cancel that sound.
The headphones should still cancel the background noise as usual, but they can’t cancel whatever noise is coming from your mouth. I wonder if this mismatch could result in some noise getting through?
If you’re wearing buds, the seal could become inadequate while your jaw is moving, so that could also explain some of the noise.
Some headphones now have internal noise cancellation, such as AirPods Pro and Max. I can hear it working when I’m chewing something crunchy or when I’m using my electric toothbrush and toggling between transparency and NC modes. Kinda curious if some other cans have this as well, it’s a nice feature. There are microphones inside the cup listening to internal sounds and cancelling those out as well as external sounds.
Theoretically, that could help a little bit, but it won’t change the fact that the ear canal is only the gateway to the organ where hearing actually takes place. Due to bone conduction, the crunchy noises can take a shortcut and bypass the outer ear completely.
It still works pretty well, not as effective as regular external NC of course, but the difference between transparency and isolation modes when chewing crunchy foods or using my electric toothbrush is very noticeable. Now I’m going to have to do a bit of an experiment with bone conduction headphones from a friend and ANC mode to see how well it’s working.
Sounds really cool. Let me know how that works out.
noise cancellation should be better at adjusting for sounds which occur for longer periods of time. it takes time to calculate the inversion, the amplitude, the frequency, the emission and line them up.
What does popcorn sound like?
It goes "pop, pop, pop," then "crunch, crunch, crunch."
A static type sound can occur while biting where you eustachian tubes are cleared. The same thing can happen when yawning (it is why yawning is encouraged when feeling inner ear stress while taking off in an airplane).
It happens without earbuds too, but might be more noticable.
I can personally pop those voluntarily, as I’m a scuba diver, and you have to clear your ears quite frequently.