4 ms·

Thanks for the clarification. Learned something new today =) What I've always wondered though: can loud sounds outside the frequency range that is audible to u

by LeonM 7y ago

Thanks for the clarification. Learned something new today =) What I've always wondered though: can loud sounds outside the frequency range that is audible to us cause hearing damage? So, say we have a 120dB 60kHz audio source, would that be dangerous for our hearing? Would we be able to sense it (although not hear it)

Zenst 7y ago
From my understanding too damage the hearing, the sound would have to resonate part of the ear enough to cause damage and if any part resinated, we would hear it. You may get cases in which two inaudible frequencies could produce a harmonic that we could hear, though unsure of any examples in this instance. You may well find though that some frequencies, which not audible by the human ear, may have some effect upon another part of the body. Though I do hope we don't end up having to carry bats in canary cages everytime we go down to the shops. But another way to look at this is - if there was some way sound could be used to harm somebody in any way, then it would have been weaponized. With that in mind - https://en.wikipedia.org/wiki/Sonic_weapon https://en.wikipedia.org/wiki/Sonic_weapon
- amelius 7y ago
  See also: harmonic distortion.
mncharity 7y ago
"It is known that exposure to noise of a certain frequency does not induce a higher TS at that frequency, but rather at 0.5 to 2 octaves above that frequency, depending on the species"[1] ("auditory threshold shift (TS)"). [1] https://www.frontiersin.org/articles/10.3389/fnagi.2015.00007/full https://www.frontiersin.org/articles/10.3389/fnagi.2015.0000... A meta observation: When the internet was new, and then the web, there was a puzzle of how society might adapt to information becoming more easily accessible than it had been. Bomb making instructions was a commonly used example. Society responded narrowly, by for instance outlawing such instructions. There's an entwined puzzle around understanding information. If science education someday fails less pervasively, how might society adapt? It's perhaps not a near-term challenge, but maybe something to think about.
- whenchamenia 7y ago
  Bomb making intructions are not illegal however.
creeble 7y ago
60kHz isn't really an audio source, at that frequency it would (or used to be, anyway) be classified as an RF source. Marconi operated in frequencies even lower, 14-30kHz, at many thousands of watts from Alexanderson alternators[0]. Dogs were not happy near these stations. https://en.wikipedia.org/wiki/Alexanderson_alternator https://en.wikipedia.org/wiki/Alexanderson_alternator edit: added link, lowered frequency range.
- tomxor 7y ago
  > 60kHz isn't really an audio source, at that frequency it would (or used to be, anyway) be classified as an RF source. It would not be classified as an RF source. Frequency does not redefine the medium. Sounds waves above 20KHz are usually referred to as ultrasound, but it is still sound. More specifically, it is still a compression wave in matter. EM waves are a completely different medium. I presume you are conflating the two through the existence of this machine, the mechanical nature of it's source of oscillation no doubt created compression waves in the air of the same frequency as a side effect (Pretty sure Dogs don't have RF receivers). Whereas now we use solid state oscillators, and so your dog doesn't care about your various RF devices.
  - creeble 7y ago
    I conflate the two because I was temporarily nuts. Doh! Of course ultrasound exists, and can exist in air up to the GHz range (not for very far). Anyway, sorry for misinfo and thanks for the correction.
    - tomxor 7y ago
      No worries. It's probably not helped by the fact that RF starts at around 20 KHz in EM at the same frequency where human hearing range ends in sound waves. So it's fairly easy to read a bunch of statements about frequency ranges and then mix up mediums, especially when EM contains a bunch of seemingly very different things, light, RF, xrays etc.

by LeonM 7y ago

Zenst 7y ago

From my understanding too damage the hearing, the sound would have to resonate part of the ear enough to cause damage and if any part resinated, we would hear it. You may get cases in which two inaudible frequencies could produce a harmonic that we could hear, though unsure of any examples in this instance. You may well find though that some frequencies, which not audible by the human ear, may have some effect upon another part of the body. Though I do hope we don't end up having to carry bats in canary cages everytime we go down to the shops. But another way to look at this is - if there was some way sound could be used to harm somebody in any way, then it would have been weaponized. With that in mind - https://en.wikipedia.org/wiki/Sonic_weapon https://en.wikipedia.org/wiki/Sonic_weapon

amelius 7y ago
See also: harmonic distortion.

mncharity 7y ago

"It is known that exposure to noise of a certain frequency does not induce a higher TS at that frequency, but rather at 0.5 to 2 octaves above that frequency, depending on the species"[1] ("auditory threshold shift (TS)"). [1] https://www.frontiersin.org/articles/10.3389/fnagi.2015.00007/full https://www.frontiersin.org/articles/10.3389/fnagi.2015.0000... A meta observation: When the internet was new, and then the web, there was a puzzle of how society might adapt to information becoming more easily accessible than it had been. Bomb making instructions was a commonly used example. Society responded narrowly, by for instance outlawing such instructions. There's an entwined puzzle around understanding information. If science education someday fails less pervasively, how might society adapt? It's perhaps not a near-term challenge, but maybe something to think about.

whenchamenia 7y ago
Bomb making intructions are not illegal however.

creeble 7y ago

60kHz isn't really an audio source, at that frequency it would (or used to be, anyway) be classified as an RF source. Marconi operated in frequencies even lower, 14-30kHz, at many thousands of watts from Alexanderson alternators[0]. Dogs were not happy near these stations. https://en.wikipedia.org/wiki/Alexanderson_alternator https://en.wikipedia.org/wiki/Alexanderson_alternator edit: added link, lowered frequency range.

tomxor 7y ago
> 60kHz isn't really an audio source, at that frequency it would (or used to be, anyway) be classified as an RF source. It would not be classified as an RF source. Frequency does not redefine the medium. Sounds waves above 20KHz are usually referred to as ultrasound, but it is still sound. More specifically, it is still a compression wave in matter. EM waves are a completely different medium. I presume you are conflating the two through the existence of this machine, the mechanical nature of it's source of oscillation no doubt created compression waves in the air of the same frequency as a side effect (Pretty sure Dogs don't have RF receivers). Whereas now we use solid state oscillators, and so your dog doesn't care about your various RF devices.
- creeble 7y ago
  I conflate the two because I was temporarily nuts. Doh! Of course ultrasound exists, and can exist in air up to the GHz range (not for very far). Anyway, sorry for misinfo and thanks for the correction.
  - tomxor 7y ago
    No worries. It's probably not helped by the fact that RF starts at around 20 KHz in EM at the same frequency where human hearing range ends in sound waves. So it's fairly easy to read a bunch of statements about frequency ranges and then mix up mediums, especially when EM contains a bunch of seemingly very different things, light, RF, xrays etc.