5 ms·

Many people either cannot hear very low frequency sound, and they cannot understand what it’s like for those of us who can. The sounds don’t necessarily get lo

by blunte 7y ago

Many people either cannot hear very low frequency sound, and they cannot understand what it’s like for those of us who can. The sounds don’t necessarily get louder at night - there are just fewer competing sounds to mask them. Earplugs and other sound barriers make it worse by filtering out higher frequency sounds, making the remaining VLF sounds seem louder. VLFs also penetrate earth, stone, concrete, etc. And because of their long periods, especially when accidentally synced with parallel walls, some locations in your house can behave like an amplifier. There’s no real solution other than moving, and there’s no guarantee that human progress will not catch up with you in your next location.

riku_iki 7y ago
Do you have any citations to support this claim?..
- deleted 7y ago
  [deleted]
- DocNoise 7y ago
  Most of what I am writing is pretty basic otoneurological knowledge. Researchers like Bohne, Harding, Dallos, Salt, Lichtenhan, Hudspeth, Moller, Kugler, Drexel et al. have published extensively on this issue. Some links to peer-revieved literature are listed in my Stackexchange post.
crazygringo 7y ago
I have never heard of this and have a hard time believing it but I’m curious. What causes “low frequency sound” for you? And why do you think other people can’t hear it? At low frequencies tones degrade into individual pulses but can still be heard/felt. Noise-cancelling headphones actually work best with low frequencies like train and plane noise... do those help you? Googling “VLF” only gives results about radio waves, none I can find referring to sound waves...
- blunte 7y ago
  i’m not going to post the same reply twice, but if you would read my reply to a sibling post you’ll see what i’m talking about.
  - crazygringo 7y ago
    Thanks, and someone else posted [1] so now I could look for more info on it! I'm now extremely curious -- what do noise-cancelling headphones do for you? You can see here [2] that Bose's QC35's reduce the lowest frequencies (down to 20 Hz) by between 10 and 30 dB -- and the Wikipedia link suggests that the Hum is in the range of 32-80 Hz, so is certainly covered. If they make a difference, that could indicate that you truly do have a kind of extreme sensitivity there, while if they don't, it could be another (real but non-auditory) phenomenon that your ear/brain is interpreting as sound, e.g. tinnitus. [1] https://en.wikipedia.org/wiki/The_Hum https://en.wikipedia.org/wiki/The_Hum [2] https://www.rtings.com/headphones/1-2/graph#565/2090 https://www.rtings.com/headphones/1-2/graph#565/2090
    - blunte 7y ago
      I don't think they would be particularly helpful for sleeping. Firstly, they would need to have very good microphone sensitivity to detect the (very?) low frequencies or at least the low sound pressures of those low freqs. Also, when I tried the new big Sony noise canceling headphones (very highly rated), I found the sensation somewhat unsettling. They did indeed shut out practically every external sound (in a big store, not at home in bed), but I perceived some kind of constant subtle positive air pressure in my head similar to what you feel about half a meter under water. My solution now in the rare case where I'm in a location that bothers me is to use some low speed fan to create lower frequency white noise. Also, either I've been luckier the last few years where I've lived or I'm becoming less sensitive to it, because I don't get bothered as often.
- egypturnash 7y ago
  So about a year before I moved out of Seattle I started hearing this HUM around the University District. It was low pitched but it was everywhere. And it was especially in my bedroom. All night long. My sleep became a lot less sound. My boyfriend never heard it. Ever. He’d sleep right next to me. His ears just didn’t go down that low, I guess. Or maybe my skull resonated with this noise better than his did, I dunno. I have no idea what caused it. It went down over time, but I’d still hear it pretty much every night I slept in my apartment. Sleep elsewhere and it was gone. I moved to another city. It didn’t follow me. I’ve mostly forgotten how glad I am to not have that low frequency hum be a constant presence in my life. Thanks for reminding me how grateful I should be for it being gone! ️
jdietrich 7y ago
As a trained sound engineer, I don't find this explanation wholly plausible. Human hearing is increasingly less sensitive at low frequencies; the threshold of hearing is typically around 60dB at 20Hz and 72dB at 10Hz. Anyone who has configured a large public address system knows that vast amounts of power are needed to deliver useful response at these frequencies; many systems simply fake the presence of low bass by tuning in a big peak at 40 or 50Hz, which requires two or three orders of magnitude less power. Structure-borne noise is a real problem in many buildings, but I'm aware of very few instances of neighbourhood-wide noise problems at very low frequencies. https://en.wikipedia.org/wiki/Equal-loudness_contour https://en.wikipedia.org/wiki/Equal-loudness_contour
- blunte 7y ago
  I can’t say whether it is an ear hearing or some other sensitivity to resonance (of the skull?). The sensation is stronger on one side/ear, and it feels like the pressure you feel if someone goes “puh” softly in your ear in a quiet room... except that it happens over and over at a low frequency. I have experienced it in several different places. One place was at college on the cliffs overlooking the Mississippi river, and I suspect it was from the boats that push barges (cargo) down the river. Other places have been near heavy freight train routes, particularly when a train is idling somewhere within perhaps a mile. It’s like if a big truck is idling a few houses down the street in a quiet neighborhood. In one location in the mountains of Colorado, the sound could be heard a many locations throughout the valley. I know this because i drove around in the quiet and remote regions, stopping periodically to listen. Some spots were impressively loud, and others were not audible. In that environment I suspect it was due to wind over the mountain ridge (sharp edged on one side, and the wind would cause a pressure differential to build until it would break and the air would take a chaotic path briefly). This is similar to what you see and hear with a fireplace where the fire is burning mostly on one side of a log, but the air flows in a way that creates a pressure differential... and it may cause a puff puff puff pattern that is both audible and visible (flame leaping around the other side of the log exactly at the moment you hear the puff).
  - specialist 7y ago
DocNoise 7y ago
Just realized that Stackexchange is currently showing only an abridged version of my blurb on the question of "adaption to LFN (low frequency noise)", so I paste the long version below. Links to literature can be found in my other post(s). I don't cover the involvement of the otolith organs (yet) but that's your connection of a low-frequency sound stimulus to the sensation of (whole body) vibration, dizziness, balance problems, blurred vision, changes in peripheral blood flow and breathing problems. --- Very quickly and totally from the top of my head: Traffic noise is in many cases dominated by low frequencies, with the whole spectrum somewhat similar to a distorted 1/f function, with a few tonal peaks for exhaust noise and tyre/tread sounds. Now add the structure you are living in: "excellent sound insulation" in the EU is (still) dB(A)-focused, meaning architects and planners are aiming for a "wow" effect in noise reduction by eliminating that what's easy to eliminate - high and mid frequencies, ignoring mostly the low (and energy-rich) frequencies, which are incidentally the ones the A-weighing of noise is (historically) ignoring as well. As a result, you are basically living in what's known as a low-pass filter, one that is also "drawing" tonal peaks (resonances, room nodes) out of that low-frequency noise mixture. At first, your cochlea's short-term adaption mechanisms will do their job well and tone down signals that are not meaningful (MOC reflex). Over time however, the presence of low-level tonal, continuous sounds can damage ("wear out") a specific sensor type necessary for this reflex to work. As a result, even inaudible LFN noise can, over time, lead to a distal sensitization effect. In many cases the culprit is actually not the traffic noise itself, but HVAC installations like heat pumps, A/Cs and gas turbines. The effect of "I can hear too much" (being aware of noises) as a result of sub-threshold LFN-exposure is known in the medical literature as a symptom of VAD stage I / II and in fact quite common in the urban population. Certain medications (Gentamycine, cis-platines) as well as organic solvents (acetone) and some disinfectants can speed up this process, which is non-reversible and poses a risk factor for suffering atypical (early onset) hearing loss later on... The "I hear too much" effect has been quite a solid indicator of long-term, low-level IS/LFN noise pollution. To be on the safe side and to rule out a sub-threshold LFN-problem, you should an have an acoustician do a "LCeq-LAeq" (should not be more than 3-4dB) and an unweighted (FFT) spectrogram to see if there is a constant tonal peak below, say, 50Hz. Also, try to wear good earplugs like UVEX Whisper or UVEX Whisper Plus at night until you can rule out any constant / nocturnal IS/LFN immissions into your place.
DocNoise 7y ago
There is a difference between "being able to hear" very low frequencies and a situation where the inner ear has been sensitized - in many cases through a continuous LFN immission that's slightly below the average hearing threshold. If the exposure is constant, the dampening mechanism that is managing the adaption of the cochlea to sound of various intensities can "wear out" on a cellular level and the ear is basically reverting back to it's original (= super sensitive) state. The process of sensitization can also be accelerated/caused through the presence of ototoxic substances like certain organic solvents, desinfectants or antibiotics. Persons with this type of cochlear damage will experience a tiny low-frequency tonal peak in an otherwise "normal" sound spectrum as almost painfully loud, booming (spread out in frequency) and/or as a pressure on the ear. This damage will not show up in standard hearing tests, in fact, pure-tone audiometry will show above-average results. Currently, only DPOAE testing could in theory reveal this type of (rather common) cochlear damage in a non-invasive way. Even though not totally understood, there is epidemiological evidence that this type of aural sensitization is connected with (read: the cause of) disrupted sleep, higher cortisol levels and thus a heightened risk of infections, cardiovascular disease. The lack of sleep frequently leads to depression and anxiety disorders. ... more here: https://biology.stackexchange.com/questions/30101/do-our-ears-or-brains-gradually-adapt-to-noise-pollution/86184#86184 https://biology.stackexchange.com/questions/30101/do-our-ear...
- blunte 7y ago
  I wonder if it's any relation to other heightened sensitivities, such as to bright light (compared to how other people handle it), lots of competing sounds (large loud halls full of people having independent conversations), and just general hyper-awareness of everything around oneself. Whether it's accepted or not as "a thing", the book "The Highly Sensitive Person" did mostly describe me. I read the book only recently, so I didn't develop the sensitivities as a result of reading about them :).
  - DocNoise 7y ago
    It is important to stress that the mechanism described are completely disconnected from so-called psychological aspects "personality traits" and general sensory processing (like falling into the HSP definition). Elaine Aaron's work is remarkable from a scientific standpoint but should also encourage people to pay more attention to the type and amount of external stimuli we expose ourselves to. The effect of being unable to follow a conversation in a noisy environment however, IS a solid indicator of the processes I describe (you might want to look up "hidden hearing loss" - Kujawa & Libermann have published on this phenomenon).

by blunte 7y ago

riku_iki 7y ago

Do you have any citations to support this claim?..

deleted 7y ago
[deleted]
DocNoise 7y ago
Most of what I am writing is pretty basic otoneurological knowledge. Researchers like Bohne, Harding, Dallos, Salt, Lichtenhan, Hudspeth, Moller, Kugler, Drexel et al. have published extensively on this issue. Some links to peer-revieved literature are listed in my Stackexchange post.

crazygringo 7y ago

I have never heard of this and have a hard time believing it but I’m curious. What causes “low frequency sound” for you? And why do you think other people can’t hear it? At low frequencies tones degrade into individual pulses but can still be heard/felt. Noise-cancelling headphones actually work best with low frequencies like train and plane noise... do those help you? Googling “VLF” only gives results about radio waves, none I can find referring to sound waves...

blunte 7y ago
i’m not going to post the same reply twice, but if you would read my reply to a sibling post you’ll see what i’m talking about.
- crazygringo 7y ago
  Thanks, and someone else posted [1] so now I could look for more info on it! I'm now extremely curious -- what do noise-cancelling headphones do for you? You can see here [2] that Bose's QC35's reduce the lowest frequencies (down to 20 Hz) by between 10 and 30 dB -- and the Wikipedia link suggests that the Hum is in the range of 32-80 Hz, so is certainly covered. If they make a difference, that could indicate that you truly do have a kind of extreme sensitivity there, while if they don't, it could be another (real but non-auditory) phenomenon that your ear/brain is interpreting as sound, e.g. tinnitus. [1] https://en.wikipedia.org/wiki/The_Hum https://en.wikipedia.org/wiki/The_Hum [2] https://www.rtings.com/headphones/1-2/graph#565/2090 https://www.rtings.com/headphones/1-2/graph#565/2090
  - blunte 7y ago
    I don't think they would be particularly helpful for sleeping. Firstly, they would need to have very good microphone sensitivity to detect the (very?) low frequencies or at least the low sound pressures of those low freqs. Also, when I tried the new big Sony noise canceling headphones (very highly rated), I found the sensation somewhat unsettling. They did indeed shut out practically every external sound (in a big store, not at home in bed), but I perceived some kind of constant subtle positive air pressure in my head similar to what you feel about half a meter under water. My solution now in the rare case where I'm in a location that bothers me is to use some low speed fan to create lower frequency white noise. Also, either I've been luckier the last few years where I've lived or I'm becoming less sensitive to it, because I don't get bothered as often.
egypturnash 7y ago
So about a year before I moved out of Seattle I started hearing this HUM around the University District. It was low pitched but it was everywhere. And it was especially in my bedroom. All night long. My sleep became a lot less sound. My boyfriend never heard it. Ever. He’d sleep right next to me. His ears just didn’t go down that low, I guess. Or maybe my skull resonated with this noise better than his did, I dunno. I have no idea what caused it. It went down over time, but I’d still hear it pretty much every night I slept in my apartment. Sleep elsewhere and it was gone. I moved to another city. It didn’t follow me. I’ve mostly forgotten how glad I am to not have that low frequency hum be a constant presence in my life. Thanks for reminding me how grateful I should be for it being gone! ️

jdietrich 7y ago

As a trained sound engineer, I don't find this explanation wholly plausible. Human hearing is increasingly less sensitive at low frequencies; the threshold of hearing is typically around 60dB at 20Hz and 72dB at 10Hz. Anyone who has configured a large public address system knows that vast amounts of power are needed to deliver useful response at these frequencies; many systems simply fake the presence of low bass by tuning in a big peak at 40 or 50Hz, which requires two or three orders of magnitude less power. Structure-borne noise is a real problem in many buildings, but I'm aware of very few instances of neighbourhood-wide noise problems at very low frequencies. https://en.wikipedia.org/wiki/Equal-loudness_contour https://en.wikipedia.org/wiki/Equal-loudness_contour

blunte 7y ago
I can’t say whether it is an ear hearing or some other sensitivity to resonance (of the skull?). The sensation is stronger on one side/ear, and it feels like the pressure you feel if someone goes “puh” softly in your ear in a quiet room... except that it happens over and over at a low frequency. I have experienced it in several different places. One place was at college on the cliffs overlooking the Mississippi river, and I suspect it was from the boats that push barges (cargo) down the river. Other places have been near heavy freight train routes, particularly when a train is idling somewhere within perhaps a mile. It’s like if a big truck is idling a few houses down the street in a quiet neighborhood. In one location in the mountains of Colorado, the sound could be heard a many locations throughout the valley. I know this because i drove around in the quiet and remote regions, stopping periodically to listen. Some spots were impressively loud, and others were not audible. In that environment I suspect it was due to wind over the mountain ridge (sharp edged on one side, and the wind would cause a pressure differential to build until it would break and the air would take a chaotic path briefly). This is similar to what you see and hear with a fireplace where the fire is burning mostly on one side of a log, but the air flows in a way that creates a pressure differential... and it may cause a puff puff puff pattern that is both audible and visible (flame leaping around the other side of the log exactly at the moment you hear the puff).
- specialist 7y ago

DocNoise 7y ago

Just realized that Stackexchange is currently showing only an abridged version of my blurb on the question of "adaption to LFN (low frequency noise)", so I paste the long version below. Links to literature can be found in my other post(s). I don't cover the involvement of the otolith organs (yet) but that's your connection of a low-frequency sound stimulus to the sensation of (whole body) vibration, dizziness, balance problems, blurred vision, changes in peripheral blood flow and breathing problems. --- Very quickly and totally from the top of my head: Traffic noise is in many cases dominated by low frequencies, with the whole spectrum somewhat similar to a distorted 1/f function, with a few tonal peaks for exhaust noise and tyre/tread sounds. Now add the structure you are living in: "excellent sound insulation" in the EU is (still) dB(A)-focused, meaning architects and planners are aiming for a "wow" effect in noise reduction by eliminating that what's easy to eliminate - high and mid frequencies, ignoring mostly the low (and energy-rich) frequencies, which are incidentally the ones the A-weighing of noise is (historically) ignoring as well. As a result, you are basically living in what's known as a low-pass filter, one that is also "drawing" tonal peaks (resonances, room nodes) out of that low-frequency noise mixture. At first, your cochlea's short-term adaption mechanisms will do their job well and tone down signals that are not meaningful (MOC reflex). Over time however, the presence of low-level tonal, continuous sounds can damage ("wear out") a specific sensor type necessary for this reflex to work. As a result, even inaudible LFN noise can, over time, lead to a distal sensitization effect. In many cases the culprit is actually not the traffic noise itself, but HVAC installations like heat pumps, A/Cs and gas turbines. The effect of "I can hear too much" (being aware of noises) as a result of sub-threshold LFN-exposure is known in the medical literature as a symptom of VAD stage I / II and in fact quite common in the urban population. Certain medications (Gentamycine, cis-platines) as well as organic solvents (acetone) and some disinfectants can speed up this process, which is non-reversible and poses a risk factor for suffering atypical (early onset) hearing loss later on... The "I hear too much" effect has been quite a solid indicator of long-term, low-level IS/LFN noise pollution. To be on the safe side and to rule out a sub-threshold LFN-problem, you should an have an acoustician do a "LCeq-LAeq" (should not be more than 3-4dB) and an unweighted (FFT) spectrogram to see if there is a constant tonal peak below, say, 50Hz. Also, try to wear good earplugs like UVEX Whisper or UVEX Whisper Plus at night until you can rule out any constant / nocturnal IS/LFN immissions into your place.

DocNoise 7y ago

There is a difference between "being able to hear" very low frequencies and a situation where the inner ear has been sensitized - in many cases through a continuous LFN immission that's slightly below the average hearing threshold. If the exposure is constant, the dampening mechanism that is managing the adaption of the cochlea to sound of various intensities can "wear out" on a cellular level and the ear is basically reverting back to it's original (= super sensitive) state. The process of sensitization can also be accelerated/caused through the presence of ototoxic substances like certain organic solvents, desinfectants or antibiotics. Persons with this type of cochlear damage will experience a tiny low-frequency tonal peak in an otherwise "normal" sound spectrum as almost painfully loud, booming (spread out in frequency) and/or as a pressure on the ear. This damage will not show up in standard hearing tests, in fact, pure-tone audiometry will show above-average results. Currently, only DPOAE testing could in theory reveal this type of (rather common) cochlear damage in a non-invasive way. Even though not totally understood, there is epidemiological evidence that this type of aural sensitization is connected with (read: the cause of) disrupted sleep, higher cortisol levels and thus a heightened risk of infections, cardiovascular disease. The lack of sleep frequently leads to depression and anxiety disorders. ... more here: https://biology.stackexchange.com/questions/30101/do-our-ears-or-brains-gradually-adapt-to-noise-pollution/86184#86184 https://biology.stackexchange.com/questions/30101/do-our-ear...

blunte 7y ago
I wonder if it's any relation to other heightened sensitivities, such as to bright light (compared to how other people handle it), lots of competing sounds (large loud halls full of people having independent conversations), and just general hyper-awareness of everything around oneself. Whether it's accepted or not as "a thing", the book "The Highly Sensitive Person" did mostly describe me. I read the book only recently, so I didn't develop the sensitivities as a result of reading about them :).
- DocNoise 7y ago
  It is important to stress that the mechanism described are completely disconnected from so-called psychological aspects "personality traits" and general sensory processing (like falling into the HSP definition). Elaine Aaron's work is remarkable from a scientific standpoint but should also encourage people to pay more attention to the type and amount of external stimuli we expose ourselves to. The effect of being unable to follow a conversation in a noisy environment however, IS a solid indicator of the processes I describe (you might want to look up "hidden hearing loss" - Kujawa & Libermann have published on this phenomenon).