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lstnsound writes in Why noise-cancellation isn't all its cracked up to be:

Neat, right? Well....not exactly. Unfortunately, this technology comes with its fair share of flaws. The opposing sound waves generated by active noise cancellation technology end up blocking key parts of the sound spectrum (aka your music). With key parts of your music blocked, your ears are forced to work harder to create sound. This creates ear fatigue and will leave your ears more fatigued than standard headphones

Is it true, that there are negative effects of active-noise-canceling headphones for the ears?

Christian
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    I'm not sure if one can say that the ears "create" sound. The claim seems plausible (causing fatigue), but not by the proposed mechanism. I'm curious to see what will come of this. – T. Sar May 16 '17 at 15:52
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    I think "fatigue" may be the wrong word (though I'm not sure what would be better), as the sound pressure levels involved are not likely to be very high. There may be a mental fatigue associated with trying to find frequencies we expect to be there but aren't, but I don't believe this could be any more detrimental than that. I think this article is mostly written based on personal experience, not tested evidence. I think the author is mixing auditory damage with mental fatigue... (I personally think he's right about sound quality being diminished however) – Aaron May 16 '17 at 15:57
  • Is this a notable claim? Can you find it repeated someplace where the claimant doesn't have something to sell? – Reinstate Monica -- notmaynard May 16 '17 at 16:27
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    Anecdotally I found the opposite, wearing them in noisy factories made me feel less fatigued than wearing nothing. I guess having an office next to a running bench saw isn't what they tested here though. – daniel May 16 '17 at 16:29
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    Ears "create sound"? Yikes. – PoloHoleSet May 16 '17 at 17:20
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    Yeah, I don't know what this means: "your ears are forced to work harder to create sound." –  May 16 '17 at 17:30
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    If hearing is like sight, your brain will fill in gaps if its necessary to make sense of it. That's how optical illusions work. I have doubts this can "fatigue" anything more than if your brain didn't have to do it. –  May 16 '17 at 17:33
  • I suspect that they meant "create the idea of sound" and that the things that would be fatigued would be ear-specific bits of brain, rather than the ears themselves. I don't think that the poor wording invalidates the claim, though. On whether or not it's accurate, I have no information. I do note that the claim appears to be being made in response to a specific scenario (noise-cancelling while listening to music, rather than noise-cancelling for silence). That seems pertinent. – Ben Barden May 16 '17 at 18:42
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    @iamnotmaynard: Claims made by motivated manufacturers and retailers are definitely in scope (although telling whether anyone actually reads/believes this stuff - and is therefore worth repeating - is tricky). – Oddthinking May 16 '17 at 23:23
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    When the diaphragm of the headphones moves, to cancel a sound wave from outside, it doesn't cause your eardrum to move. In fact it balances out the pressure wave so that your eardrum doesn't move. So if you're imagining that the constant adjustments of noise cancelling headphones would cause fatigue, then the opposite is probably the case. Anecdotally, I find them very relaxing, as long as the headphones themselves fit your ears comfortably. – Richard May 16 '17 at 23:28
  • I have noticed that wearing noise-cancelling headphones for too long can cause pain once the headphones are removed even with no music playing; it doesn't seem to be a fatigue issue but something inner-ear related, though. The headphones responding to sudden changes in pressure can also cause an odd sensation/noise or even cause the headphones to turn off for a moment if the battery is low, like when a door closes quickly nearby (I've mainly experienced this on trains). – JAB May 16 '17 at 23:36
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    @daniel same here in a noisy office environment. Blocking out the constant chatter of coworkers made me less fatigued, more productive, and stopped me having regular anxiety attacks. – jwenting May 17 '17 at 06:39
  • @fredsbend - "if hearing is like sight" - that's a pretty big qualifier, IMO. BTW, I'm not interpreting that to say that you are making that particular claim, just that you're trying to give the benefit of the doubt for something that seems to make no sense, as claimed. – PoloHoleSet May 17 '17 at 14:37
  • @Polo I don't think it's that big of a qualifier. Both senses are processed in the brain and heavily subject to over-stimulation. In a loud room, you can still hear just the person you want to, the one you're talking to. Noise discrimination is a real thing. What I'm quick to challenge is that practicing it can "fatigue" your hearing. I don't know what "fatigue" is even supposed to mean, in this context. –  May 17 '17 at 19:53
  • @fredsbend - Filling in "gaps" in our visual field is readily apparent if a color is off or something is missing. There is no set level of saturation at different frequencies for sound. If there was no "c#" in a section of music, it might be because it's "missing," or it might not supposed to be there. There would be no reason for the brain to identify missing frequencies in music or sound as missing frequencies. Vision and hearing *are* different. Very different. Different stimiuli, different organs, processed by different parts of the brain, that are developed to different levels. – PoloHoleSet May 17 '17 at 20:01
  • @Polo I can think of several reasons why you might "hear" something that isn't there. You can follow up on the biology site, if you want. I'm rapidly losing interest. –  May 17 '17 at 23:31
  • @PoloHoleSet Your ears most definitely do fill in holes in what you hear. The "missing fundamental" is a classic example, where you can "hear" a sound frequency that doesn't actually exist. We also will fill in missing parts of sounds that we perceive as being covered up by other sounds, even when those missing parts don't actually exist. – TheBlackCat May 19 '17 at 16:26
  • @Richard Most noise-canceling headphones are not perfect, however, so the produced waveform isn't always an exact amplitude-matched inversion of the input (most noticeable in the fact that the amplitude isn't always the same [usually smaller past the limits of the headphones' power supply], but shape is also affected). – JAB May 20 '17 at 19:27
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    @PoloHoleSet The brain filling up the gaps to put sound where there is none is a very real effect. There is a selection of gifs that can be "heard" because they cause the brain to expect sound, even if the images are completely mute, [like this pretty popular one](https://nerdist.com/sound-silent-gif-power-lines/). – T. Sar Dec 21 '17 at 16:36
  • @T.Sar - I can imagine a sound, but there was no sensation of "hearing" that sound when I saw the gif. At no point was my brain processing it as if there was a sound coming through my earbuds. – PoloHoleSet Dec 21 '17 at 17:10
  • @T.Sar - Also, that is the brain filling in gaps not based on missing sounds, but based on ***visual cues.*** If there is a song with, literally, dozens to hundreds of different notes and tones being combined in any instant, do we have anything to suggest that the brain cares enough to fill the gap of one tone when there are so many others? If it's not familiar, how would it know one is missing? If it is familiar, it would just call the memory, the same as with the full spectrum, and we don't necessarily see a mechanism of synthesizing a sound like the ear does with that phenomenon. – PoloHoleSet Dec 21 '17 at 17:13
  • In any case, looping back to @TheBlackCat talking about the missing fundamental, in that case the brain seems to be making assumptions about the missing note, instead of fully processing the actual sound, which sounds like a shortcut vs. the extra work of generating a sound-brain signal. Do we understand the exact mechanism at work, or we just know what the final perception is? – PoloHoleSet Dec 21 '17 at 17:53
  • @PoloHoleSet Fair enough. You have a good point there. Just keep in mind I'm not claiming that it is the ears that create that sound. – T. Sar Dec 21 '17 at 17:53
  • @T.Sar - and I'm not claiming definitively that it's not, just my suspicion that it is a very different thing going on vs. the claim. I put a general follow-up comment as you were posting yours, asking if we even know what's going on when that happens. – PoloHoleSet Dec 21 '17 at 17:54

1 Answers1

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No. It's the opposite: noise cancelling headphones typically reduce fatigue.

The opposing sound waves generated by active noise cancellation technology end up blocking key parts of the sound spectrum (aka your music).

Not correct. The noise cancellation blocks outside sound, but doesn't not affect the spectrum of the music. Overall the transfer function from the input to the ear drum is very similar to that of a conventional headphone. The music is simply added to the cancellation signal and not affected by it.

With key parts of your music blocked, your ears are forced to work harder to create sound.

Not correct. Healthy ears don't create sound. Key parts of the music are not blocked.

This creates ear fatigue and will leave your ears more fatigued than standard headphones - this is why you'll never see musicians using noise-canceling headphones.

Not correct. I work with musicians and do listening professionally. Many musicians love noise cancelling head sets and use them all the time. Flying is pretty hard on the ears and noise cancelling headphones significantly reduce noise induced fatigue, to the point that I can work when I come off a plane. Which I can't without noise cancellation.

There is well established correlation between stress and noise levels https://en.wikipedia.org/wiki/Health_effects_from_noise and reduction of noise will result almost always in less stress, not more.

A side note: there are pathological conditions where the human ear actually does create sound. The inner ear has about 5000 neurons, about 20% of which are "efferent", i.e. they carry information from the brain to the inner ear. These information is used to actively tune a feedback loop that increases frequency sensitivity. Damage to these neurons or the associated hair cells can make this loop unstable and oscillation occurs which is measurable with a microphone. This is an extreme case of Tinnitus and the ears are quite literally "ringing". When working with a noise cancelling manufacturer, we found incidences where users reported significant improvement of their condition by using noise cancellation. However, that's anecdotal and as far as I know there is no solid scientific study to back this up.

Hilmar
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  • I think TFA is confusing the pressure felt from the less advanced noise cancelling cans for something else. They can get uncomfortable and cause fatigue due to that pressure, but the problem was largely fixed years ago. – dont_shog_me_bro Feb 25 '19 at 11:06