Earplugs only make it worse, because they filter out ambient noise that otherwise helps distract you from the incessant hum. Daytime is not as bad as night because of the natural activity sounds of a city.
I have read that waves and underwater currents hitting the shore (or below the shore) can cause vibrations that will translate through the earth. That could be a cause of such sounds in some parts of the world.
When I lived in the mountains of Colorado, with few people around and no industrial equipment anywhere, this hum would come and go and drive me nuts at night. I finally came to the theory that it was certain wind conditions going over the mountain ridge (across the valley), creating a pressure differential on the other side of the ridge. After the differential would reach a certain threshold, the air pattern would break up and create a pooof. This is sort of like if you are sitting in front of a campfire and the flame is going mostly on just one side of a log, but every second or so it breaks around both sides. The sound is identical, but singular. Although if it happens at a fast enough rhythm, it becomes a frequency that sounds very similar to a "hum". Of course the fire burns the wood and the conditions that make that happen change soon.
I have wondered what kind of measurement equipment it would take to try to identify the source... triangulate it somehow. I really wish I knew the definitive answers to some of these hums.
Short version: I made many attempts to track it down. Used low frequency Microphones, filters, amplifiers, etc, as well as PC Spectrogram programs to try and and visualise and record it. Visited many nearby industries etc to try and find it. But none of my attempts did any good.
As I'm a Radio Engineer I spent ages experimenting with VLF Receivers, Spectrum Analysers, etc.
One thing I noticed however was that the Hum was much worse when I was living in a quiet rural area.
One night however, I noticed that I could affect the hum by doing the swallow maneuver that divers use to equalise ear pressure. I slowly came to understand that my Hum was an internally generated sound.
Apparently there are various possible mechanisms: The simplest is blood flow near the ear. But also the tiny hairs in the ear canal actually have tiny muscles which cause feed-back or "regeneration" to make our ears more sensitive, and the frequency response of each hair cell much sharper. However at times, this regeneration can slip over into actual Oscillation.
This ability of the ear to actually generate sounds is well documented. It can actually be loud enough for a Doctor or a partner to hear. It's called Objective tinnitus.
In my case, the Hum eventually disappeared and has never returned. I suspect that it coincided with a change in blood pressure medication, but I can't be sure.
Looking back, I would suggest that it may be worth trying to amplify the sounds via a set of high-quality earphones and appropriate filters, etc, using the headphones as microphones.
'In 1951, Cage visited the anechoic chamber at Harvard University. An anechoic chamber is a room designed in such a way that the walls, ceiling and floor absorb all sounds made in the room, rather than reflecting them as echoes. Such a chamber is also externally sound-proofed. Cage entered the chamber expecting to hear silence, but he wrote later, "I heard two sounds, one high and one low. When I described them to the engineer in charge, he informed me that the high one was my nervous system in operation, the low one my blood in circulation." Cage had gone to a place where he expected total silence, and yet heard sound. "Until I die there will be sounds. And they will continue following my death. One need not fear about the future of music." The realization as he saw it of the impossibility of silence led to the composition of 4′33″.'
I'd like to experience that sometime, like, true silence. Have to say that my current house is very quiet (especially compared to my previous one), but there's still some background noise from outside, neighbours, the ventilation, etc. Should get a decibel meter sometime.
Anyway yes, sensory deprivation is weird.
Surely you asked other people if they also heard a hum? If they said no, what made you not focus on the ear right from the beginning?
In my case I'm single, so the question is moot.
But whatever, it is still possible that your partner also is a Hum sufferer.
You have an unrealistic expectation of Reddit. A subreddit is not an information dump for people who want to learn about a topic (for that you should look to the sidebar, or FAQ, or Wikipedia).
Its a community of people who are interested in a topic (and trolls... so many trolls) sorted by the most recent things they were talking about and whether the community wanted to talk about it. Communities don't constantly post and upvote introductory stuff in case new people happen by, but they are often responsive to questions from new people
Think of it like a clubhouse that you walked into. Right now you are standing at the bar trying to listen in on random conversations around you and saying "none of these people are talking about what I want to know in terms I can understand, some of them are even talking about whether they like the clubhouse's new decorations! WTF!".
Instead you should try joining into one of the conversations, or looking for a sign that says "new people come over here".
It's used all over the internet, and it's, by turns, a passive aggressive posture. Some acquiesce, and others enforce. The rest abandon. Linux follows a similar pattern with RTFM.
The Linux community process, as an example, has graduated to exclusion through sheer volume, with shrugs all around, as if to say the world really is just that complicated. But it's not. Inertia makes the situation more complicated than things need to be, and that disorganization (which was originally a product of the "everything is a file/lots of tiny, specialized executable programs" philosophy started with UNIX, leaves everyone blameless and) offers advantages to what I've come to refer to as trivia sherpas, who understand the seniority they've accumulated, and wish to keep things that way.
It often doesn't start as anything malicious, and some of it really is incidental, but that it stays that way is no accident. Sort of like the petroleum and automobile industry dynamic. Neither was an ideal solution for the problems they solve, but once circumstances snowballed in a certain direction, we all got stuck with these elephants in the room. Is it possible to uproot and improve the situation? I wonder...
>A subreddit for those who can control their Tensor Tympani muscle. http://en.wikipedia.org/wiki/Tensor_tympani_muscle#Voluntary...
I think it's pretty self-explanatory.
It depends a lot on the subreddit (they're essentially different websites), and of course the people. You can often find the great Walter Bright himself answering questions on D, for instance - https://www.reddit.com/user/WalterBright
Go look at like, www.reddit.com/r/gaming instead. The vast majority of reddit is not "wtf" moments.
Alternatively, it could be a resonance mode between infrasound stimuli and tension/relaxation of the tensor tympani. Eg. Pressure pulse -> TT reflex -> neural reflex drops as sound is blocked by TT -> repeat.
Total speculation, but this would explain the person-dependent experience, as well as the inefficacy of earplugs, sound dampening, etc.
Oh weird, I always assumed that was something that people could just do. It never occurred to me that there would be any particular variance in it. Oddly enough, it seems a little easier to do if I close my eyes.
I'm not sure what exactly im doing, but it feels like im contracting some muscle inside my head near the temples.
Is this normal and could this be something similar?
When you do it, you can hear a low humming, but also sounds through your mouth. Maybe this is what you mean?
It's clearer if you're wearing for example hearing protection, and open your mouth and the paths.
I'm putting a mic on the back of my head to pull the room then stereo directional mics out front to actively noise cancel the room but not the person I'm looking at in a cone that I can fiddle with. Initial tests seem to work! I'm trying to improve it with a crossover for low frequency on the jaw just under my earlobes and a mid/high driver on my temple. I think even a commercial setup for bike riders and some experimentation you might be able to find some relief. I've found them to be lacking in lower frequency which is why I'm using stronger drivers and the below the ear positioning.
Might be something to try playing with. It's pretty inexpensive. I'm using "Surface Transducers" from Adafruit and an STM32F4 Discovery board to process the noise canceling (has great FFT libs). All in my current setup is maybe $150 with a couple iterations under my belt.
What drivers are you using?
What is the grinder community? I assume not the gay dating app, I don't think that has a scene for cyberpunk body mod, but I could be wrong.
I linked to the drivers in another comment below. I think I can find better ones, but they are the most powerful I've been able to find and have good frequency response. They are also HUGE so with my test rig I look pretty silly wearing them.
Personally, I've been a member of https://biohack.me since more or less its inception but I have yet to undergo any surgery. That will change soon, and transducer earphones are second on my list.
Hence my questions, I love to compare notes.
A surgery guide for a commercial transdermal product with lots of fun pictures: http://www.cochlear.com/wps/wcm/connect/8eb51452-641c-47a5-b...
The general consensus, after much experimentation, is that the targus isn't the best site because it just doesn't conduct loudly enough. Direct bone conduction via surgery of course works well, but then there is still the issue of power and amplification.
There's been talk in the past about a non-permanent dermal retainer that could do the same thing, and this could potentially be an all-inclusive package if done correctly. That's something I'd like to look into when I have the tools and money.
The spread between mid/high on the temple/targus and mid/low on the jaw are crazy though. When you have both it is full imaging that includes a space with a frustum inside your head.
Thanks for the body mod info! If you are looking at the implants I would highly suggest tying these positions I'm suggesting. I don't think it's worth the risk for the output!
* Large Driver - https://www.adafruit.com/product/1784
* Small Driver - https://www.adafruit.com/product/1785
There is a wide range of transducers out there, if you start digging around the units can be hard to find. Sometimes they are called Exciters. This company PUI Audio makes a bunch.
The large transducers from Adafruit are such odd components. I haven't really found anything that will push that much power, but I think there are better packages for my application. They sound great with the recommended 20w amp.
Here is the STM32Discovery board I am using and the FFT libs.
I've been told by a few people that bone conduction noise canceling is impossible, but I beg to differ. I did a patent search the other day and it looks like Apple filed a patent on some bone conduction noise canceling headset concepts that use accelerometers and so did another company I've never heard of. Also in 2002 the us government funded a $100,000 research grant for it. I do a lot of AR/VR R&D, I have for about 10 years. I'm pretty convinced that selective sound isolation with bone conduction headsets is crucial to a good AR experience too but at the end of the day I'd just like to be able to go to a social gathering without a performance hangover or not want to kill my buddy because his jaw clicks when he eats.
Next step would probably to get a few of these, see if you can record the hum on a few of them, and then start experimenting.
The theory behind triangulation is simple. But in practice, it's probably really hard to make sure all microphones have the same sensitivity. The standard approach depends on sounds being quieter when they are far away, but if one mic is naturally quieter (deeper inside the house, or more absorbant material, or just more obstacles in the way) that no longer works.
The best approach would be using a phase difference to measure. Exploiting the delay due to the speed of sound.
That means you need some way to synchronize the recordings. Presuming a 20hz signal, you'd need your synchronization to be better than 0.05 seconds.
This also requires the hum waveform to be easy to match. That is, you'd need to be able to tell the phase offset by matching parts of the sound.
You could also try a 'big data' approach, just cataloging all reported cases and looking for patterns. That requires dealing with very noisy data though, as reported cases will be inconsistent. This is due to people not always being home, not everyone hearing it, and no verification of reports.
Interesing idea: use the 'bit data' approach together with wind speed and direction. The sound should be easier to hear when the wind blows it towards you. With enough data and corresponding wind data, you might have something.
Does require compensating for correlation between time of day and the wind. If wind is west in the night, and less people hear things when the wind is west, that might just be because they are sleeping.
If you're looking to measure things near or below the limits of human hearing, I'd recommend looking at microphones designed for infrasound rather than low sensitivity microphones designed to go into the ultrasonic range. PCB and Brüel & Kjær are the big names here.
Measuring infrasound is pretty difficult, unfortunately. Most audio gear has a high pass filter, which makes sense for most uses but not this. Also, pseudo-noise from air currents is often a huge source of error.
Edit: Also, note that I mean doing hardware amplification of the electrical signal in the wire coming directly from the motion of the magnet of the speaker.
Microphone size doesn't really matter that much for low frequency sound. The Earthworks M50 suggested above? I wouldn't recommend it for this application because if you're going to spend a lot of money, it might as well be on something well-suited to the application. However, the approach it takes works and can be done for much less money. Cheap omnidirectional electrets go down pretty far, and you don't need the ruler flat response of the M50. You just need amplification circuitry that doesn't filter out the low frequency stuff you want.
DSP is commonly used to correct the frequency response of microphones. However, measuring frequency response is difficult and expensive.
However, please read my post above on what I actually found.
And yes, I don't expect comparing amplitude to be useful--sound localization almost always uses TDOA/phase difference for that reason.
On Youtube, it yields several people video recording them, from Russia to Asia: https://www.youtube.com/results?search_query=strange+sounds+...
This reminds me of a YouTube video I found from someone who thought they found a UFO near the Wal-Mart parking lot one night. It was the red blinking light on top of a water tower. People are very good at convincing themselves of things.
We only have their word to go by, and it's not much use given their leaning toward supernatural and conspiracy.
This has been cited as a possible explanation for strange noises in the mountains at various locations and also as a possible cause of the infamous Dyatlov Pass incident.
Of course, other fluid dynamical instabilities could be responsible, so discounting a Karman vortex street doesn't eliminate fluid instabilities in general. A more general fluid dynamical instability is the Kelvin-Helmholtz instability: https://en.wikipedia.org/wiki/Kelvin%E2%80%93Helmholtz_insta...
Edited to remove snark
It's early in, look for the part about Vic Tandy.
I used to live right next to a busy highway, and that higher pitched white noise didn't bother me once. This unstoppable deep noise is incessantly annoying.
Wonder if it is something similar.
I like the physiological suggestions in the replies, but I don't see how an entire community could suffer from the same thing without a common cause.
Boy was I happy when they were done drilling.
Most interestingly, just a month ago they finished drilling for gas much more closely, right at the edge of the city, not even a kilometer from my house. I didn't hear anything.
My working theory here is that in the former case it was a drilling at a new location, so they must have induced vibrations into the bedrock layers that all the houses here are built on. While in the latter case there was an abandoned operation at the same spot - perhaps they re-used the hole and just drilled it deeper.
So many things could be going on underground (types and shapes of materials) that would make your location affected (or not) based on how the waves travel from each location. Maybe you were just better situated to dodge the waves of the second drill, or something didn't match the same acoustic resonance to be a problem.
...what? Did you not open the link at all? Or are you suggesting they're lying? They literally explicitly say it's an actual recording of the Windsor Hum at 11:12pm on August 24, 2011...
Seeing the video does not make me less skeptical. I don't know that they're lying, but I do not have great faith in human perception.
One of those sensory deprivation chambers?
That usually does a good job of sponging up any low-frequency vibrations so long as you don't have any harmonic issues.
If you were battling a persistent hum you'd have to engineer the floors in your house to be floating in this fashion, if not the entire house.
Not sure if commercial headphones would cover the frequency range if it's outside the norm, but Bose et al are great for rhythmic environmental noises.
To make it even more challenging, because this is a subtle sensitivity issue, and because most of us don't have identical hearing in both ears, you can't just pipe in the same volume of inverse wave to both ears. It's a really hard problem to solve.
Plus it's not very comfortable trying to sleep with big headphones on; and nighttime is the worst time for this problem.
I wonder if the hum persists during a power outage.
Cutting off the power to that island would be a good thing to try, but apparently the US is uncooperative.
I actually think it's the sound of traffic.
* The amount of walls between a mic and the outside.
* The absorbance/reflection of nearby materials, including their shape (flat surface will reflect sounds amplifying certain directions).
* The clutter between the source and receiver. Sound carries over water, not over cities or forests.
* Similarly, elevation of the receiver. Higher means less effect of clutter, and obviously, a hill in between will be an issue.
* Wind direction. Wind will blow the sound away.
It might still work with enough measurements with the same microphone, but that is not a given.
A decent backup plan would be measuring the phase difference. This is still frustrated by wind, but doesn't depend on the senstivity of the microphones.
It does require synchronization of the recordings, which might also be difficult.
Could you record with a multiple "microphone connected to a Raspberry Pi" setup, with the time synchronized using something like the NIST time signal using an RTL-SDR, or a cellular signal, or GPS, or maybe using NTP?
None of my flatmates heard that sound, so I started questioning my perception until I found another person living in the same building hearing that sound. Our bedrooms are located one below the other and the sound is most perceivable in that rooms, but we can hear that sound at other places inside the building too while others can not.
Some time later, articles in various local newspapers about that hum appeared (search for "Brummen Hamburg" if you're interested, unfortunately only articles in german), telling stories about various people along the river "Elbe" hearing that hum. I started reading about the Windsor and Bristol hum that time too.
A local politician started investigating that issue together with scientist from a technical university but - besides some theories (e.g. a big power plant) which couldn't be proven - with no success. The acousticians where cited that some of them could hear the hum at various places too, but in terms of sound level they couldn't measure it distincly from the "general" background noises of the city (with harbour, industry and much highway traffic).
In the last few years there wasn't much news about it but the hum is still there in varying intensity and duration.
You may want to read about the Kokomo, IN "hum" investigation which was traced back to an industrial source .
You're absolutely right, but there are different types of hums and many of them you can directly be linked to a source. Just to name the two loudest in my direct neighbourhood:
* Some kind of ships at slow speeds make very loud humming sounds. The loudest in my expirience are big car carriers (to be specific: Grimaldi carriers in Hamburg). The sound is very unsettling since it's at such a low frequency, that it's more "feeling" than "hearing". But the good thing is that it's over after the ship passes by.
* Some procedures in the nearby ship repair dock are very unsettling too. Especially sandblasting ship hulls is very annoying and for some reasons they mainly do it at night.
But the most distracting hum of which I was talking about in my parent comment has yet to be linked to a specific source. And it lasts much longer than my other examples, typically for days. So it has to be something which is produced only in specific conditions. This doesn't mean that this is ruling out all of your examples (e.g. large refrigerators could only be in use when the storage capacity is needed, it could be specific vessels etc.).
I was on Belle Isle last year, two times, which is a few hundred meters from Windsor, and the sound was extremely soothing for whatever reason.. I spent days on end thinking and reaearching. I finally attributed the sound to some sort of tunnel boring machinery. There are a handful of salt mines in windsor, which i discovered after seeing more than the two tunnels I was aware of, between Detroit and Windsor, in the river, on Google Earth.
I am in the habit of identifying every sound that I am exposed to consistently, which I noticed when I bought a new house. After moving I diligently inspected my HVAC system, computer fans, appliances, which neighbors parked where, and how hard they slammed their doors, etc. Not only do I identify every sound, but I also actively recognize and consider every combination of sounds.(neighbor1.carDoorSlam sounds different when my furnace is on, or furnace+fridge compressor, for example.) Once I know for certain what a sound is, I can identify it immediately, and continue with my current activity knowing that it was just some irrelevant, petty routine happening.
I can't imagine enduring a sound like that for long, while knowing I am unable to identify it; I was able to convince myself that it was due to tunnel boring; but I seldom am reminded of the sound and never disturbed by it, since I don't live in the area..
I never have quiet. Even in a hearing test with the headphones on I can hear a loud brown noise. My wife and mom say I have hearing damage but I don’t do terrible on hearing tests. I don’t do great either they just always act like it’s nothing so I don’t know what to think.
(Side note: Does BT audio do some kind of lossy compression? Why is it relevant that you mentioned it here?)
Yes. Bluetooth audio is never lossless. Proprietary Bluetooth codecs like Sony LPAC or Qualcomm AptX come close to being lossless, but they’re still lossy.
The filtered sound is pretty bad, yes, dread inducing.
I have a distinct memory of the huge stacks billowing yellow smoke, and the twists of ductwork forming structures that look like hellish versions of the buildings from a Dr Seuss story . It was simultaneously amazing and terrifying, and I couldn't take my eyes off it until it passed out of view.
Years later I'd learn about how poorer neighborhoods were in the shadows of and downwind of such places.
I don't know if this place is uniquely terrible or this is the invariable cost of steel production. But I imagine this sort of thing is common in the industrializing world today, where a lot of steel is produced. Is there an example of a "better" way to make steel?
The photos are 'impeccable' art, but the subjects are definitely 'awful'. Along with looking at a series of photos of mills, I gained a much better appreciation for the visceral disgust people have (historically) had about 'industry'. They truly look like outposts of Evil.
The sound bounces around so much, just walking around I couldn't pinpoint it on a couple nights of trying. Its wierd to hear it, but not be able to determine direction. The city figured it out.
I live about five miles from Heathrow airport. Occasionally I will have planes taking off over our house which is fairly loud and sometimes I can hear them powering up and taking off - that's quiet and distant and I can't always hear it.
When the Icelandic volcano closed the airspace a few years ago I was stuck by how quiet it was outside. Not just the lack of identifiable take-off noises but I became aware there had been an imperceptible continuous rumble. This came back when the airspace opened.
There are always aircraft in the skies, I presume this low level noise is the culmination of many distant jet engines.
Note that there is some variance in the volume of air traffic: weekend nights tend to be a lot slower than weeknights. Same for Christmas Day (and the night before and after). If "the hum" was caused by jet engines, this variance should be noticed too. The risk of misattribution is considerable, however, as industrial and other activities also tend to wind down during weekends and holidays.
Yes, I agree hence the way I worded the starting of the comment. It was more an observation that there is a lot more noise going on than is immediately obvious and noticeable.
Regarding these hums some people are reporting, given that they say ear plugs if anything increase the effect I think it is likely internally generated like the various causes of tinnitus. Possibly some infra-sound/vibration is directly detectable by some people in a similar way to magmatism is by some animals and supposedly some people. A second thought is it could be triggering / resonating something in the ear so you are physically hearing the sounds, like when you rub your eyes you see flashes. Thirdly perhaps it is purely psychological.
I've not read much about the hum phenomena and not knowingly personally experienced it my thoughts are just that, thoughts.
I think there's a bit of armchairing going on here, in that people are definitely trying the obvious already.
Part of the problem is multipath due to reflections caused by buildings, hills, trees, etc. Anytime you listen to thunder or fireworks the rumble persists due to reflections off of such things. It's incredibly difficult to algorithmically remove multipath from terrestrial sources.
As one of these suggesters - I think it's the problem lies in that the article doesn't mention this obvious first step in determining the source.
Do you really think that between the Canadian government and two universities, over the past seven years, that you are the first person to suggest this "obvious first step"?
"Since reports of it surfaced in 2011, the hum has been studied by the Canadian government, the University of Western Ontario and the University of Windsor."
Those are all the links in the article, the last one (https://www.dropbox.com/s/vi8ek3hqiof81ca/UW%20Study%20Repor...) gives us
"For the duration of the project, the Hum manifested on only a
handful of days, which made the identification of the source
difficult. Good data representative of the Hum was measured using
the stationed noise monitors. Conclusive evidence of the source
was not achieved using the NSI system since the Hum was not
present on those days that this equipment was deployed on the
river. The conclusion of the research is that the Windsor Hum does
exist and has both qualitative and quantitative characteristics
that surmise the likely source of the Hum to be from the blast
furnace operations on Zug Island."
So the main problem of the article is that it tries to make a mystery from something reasonably good investigated.
Cross border noise pollution was likely never envisioned in any international treaties, so there is no obvious legal means to resolve the problem.
The sound pressure wave is picked up by one, then some few microseconds later, it appears on the other(s) a few centimeters away.
This is pretty straightforward with ordinary sounds that dominate the signal. You could pick out the wire which was struck in a piano, and even the nodes and harmonics along its length.
It gets more difficult at lower frequencies and with quieter signals, which precisely describes this exact situation.
The noise has been narrowed down to one island that has "a few blasting operations". So stop the operations and see if the hum goes away. Then have each one restart one at a time. Or bo binary search, whatever. It doesn't matter.
The obvious takeaway here is that the city/state/province does not care. They are too deep in the pockets of those industries to make any waves at all.
Government has so little power to do anything. They are just the paid legitimizers of the corporations.
Zug Island is in Michigan (US).
Windsor is in Ontario (Canada).
The same way some fucked up people train themselves to ignore smoke detector chirps. I've known a couple of these people in my life. They managed to live with a chirping detector for weeks on end and when you bring it up they think you're making mountains out of molehills.
This one started in Summer 2016 and is going 24-7. The only times I've stopped hearing it is when I've gone on vacation; I really need to move. But finding a new place in Seattle is kind of a nightmare right now, and moving to a new city is not without its own complications!
Because, in all likelyhood, they're not suffering at all.
People vary greatly in what causes them discomfort. I imagine the population that doesn't attend to chirping smoke detectors has a strong selection bias for not suffering due to it.
I don't mind carrying reasonably heavy things for miles on foot. I remember one weekend where I had some time to spare and needed to buy a chair, so I jogged about 3 miles to a strip mall, and carried the (boxed) chair back home.
Enough people negatively comment about the weight of laptops that I believe that it matters to some people, but I honestly won't care if my mbp weighed 2 or 3 times as much as it does. I can't understand how laptop weight bothers people without some medical condition, but I also believe them when they say that heavy laptops cause them discomfort.
In retrospect, growing up canoeing for a week every Summer on the Canadian border probably has something to do with it. By the time I was 16, for the longer portages, I'd be the one to take a lighter pack on my back and throw the canoe up on my shoulders. My dad and my brother would carry the heavier packs. Learning to tune out the discomfort of walking up to a bit over a mile over uneven ground through mosquito-infested woods with a 90 lb aluminum 3-man canoe on your shoulders plus a 20 to 30 lb pack probably causes both mental and physical changes that reduce your perception of discomfort from carrying things. There's also survivorship bias, where people inclined to feel discomfort carrying heaving things for distances are likely to not return year after year to canoe areas that require portaging.
Just because you're suffering doesn't mean all people in the same situation feel any discomfort.
> it served as an uninhabited Native American burial ground for thousands of years
> The bulk of our observations from both stations do not support the hypothesis that the source of the Hum emanates from Zug Island
The leading theories are it has something to do with this mordor like place https://en.wikipedia.org/wiki/Zug_Island
Noise and vibration
In 2011, the Zug Island area was identified by Canadian scientists and Ontario's Ministry of Natural Resources as the source of mysterious rumblings and vibrations that have plagued hundreds of area residents with cyclical vibrations reportedly being felt in the ground up to fifty miles (eighty kilometres) away.
The city of River Rouge reported in the Star that it cannot afford to spend any more money on investigating the hum. They claim the City Council had already spent over $1 million to help Windsor and Ontario find the source of the noise. However, they say it likely comes from the steel mill facilities on the island.
As of April 2013, a Canadian scientist is using sound-level meters and a portable "pentangular array" of cameras and microphones to try to precisely identify the source of the sound, in order to know whom exactly to ask to fix it.
Another report released on May 23, 2014, confirmed that Zug Island was the source of the hum.
 Schmidt, Doug (September 21, 2011). "Zug Island likely culprit of Windsor hum". The Windsor Star. Postmedia Network Inc.
 "Mysterious noise escalates in Windsor, Ontario". CBC News. January 30, 2012
 Ashifa Kassam (June 7, 2016). "The 'Windsor Hum': where is the noise plaguing a city of 210,000 coming from? | World news | The Guardian"
 "River Rouge calls off search for Windsor Hum". CBC News. November 7, 2011
 Tingley, Kim (June 24, 2013). "The Sound and the Fury". OnEarth.org. NRDC
 "Mysterious Windsor Hum traced to Zug Island, Mich". CBC News. May 23, 2014
 Colin Novak (May 23, 2014). "Summary of the ‘Windsor Hum Study’ Results"
Also, does the hum change pitch a lot? With multiple sources at different frequencies, there would likely be beat frequencies. Which could be in constant flux.
And if somebody asked me anyway, I'd just say "I want to visit the town. I'm curious."
I have to say, I do miss the Schengen area. Going from the Netherlands to Germany was a breeze.
And yeah, we're vastly over simplifying. Imagine all the reflections and refractions that an urban center would introduce.
Also the sound could be reflecting downward from cloud/temp layers, greatly complicating it.
Not to say it's not possible, just super tricky.
Our living room had a window facing the street, and sometimes one could hear a low pitch humming noise that made that window shake. The first time it happened I remember wondering who would leave a delivery truck in neutral for so long.
It was really annoying, especially because when I opened the window, there wasn't a car parked outside - everything was silent. Until you listened carefully, only to confirm the hum was still there, seemingly at a distance.
So the window was reverberating to the hum. But where did it come from? Across the street there is a military academy, so I guessed the obvious guess: military experiments, of course!
The problem with that guess was that under closer inspection, the noise didn't really seem to come from that direction. Usually, one could only hear it in the afternoon, but the hum was present all week round - and around there only the military worked weekends. But it just looked it came from in between some trees far away. So I guessed differently: a big air conditioning system, some large boat, a generator in some construction yard, a concrete mixer...
The hum's amplitude would slightly vary, and the window would just hum along or even rattle annoyingly sometimes. So I guessed that if wind was a factor in modulating the hum's intensity, it would be relatively far away. Either that or it was coming from a moving source.
One day the hum simply stopped. I never found out was was behind it.
I live near Bristol, which also has a hum, and I may have heard it but my own presumption would be hearing damage, as I don't think I've looked after my ears as well as I should have. And that would go for a lot of Bristol residents too... good music scene there!
I get the impression you can measure the sounds waves just fine, the folks investigating it just have a problem locating it. Which can happen if the noise doesn't come from a point source, and/or its wave form features aren't well suitable for tracking.
It could even be causing the bones in their heads to resonate, like how those kids toothbrushes that make you hear music work.
That would explain the difficulty in locating the source.
A seismologist would probably deploy seismomters in a wide distribution near the hum area. Then record continuously for about a week. And finally use inferometry to locate the source(s).
It took me ages to understand why I was so stressed out until one evening I noticed things going peaceful all of a sudden. After that I became aware that the fan was running continuously from early morning to late evening, so I set to move out as soon as my term was over. Now I'm noticing that the building AC at the office is making the exact same low frequency, low amplitude hum when it's on and I get the exact same sensation of relief when it goes off.
Now, when I look at property, I also look for fan ducts on the walls. I also just realised that I should be looking for fan ducts inside walls if there's AC too...
I now live in an Apt complex built over where I was riding. The hum has gone. Its been replaced by another one, but I know what it is: the freezer truck supplying the 7-11 downstairs has a noisy motor and they keep it running doing the milk delivery. No underpants rides at night for me.
Their solution is to use a very long array (i.e., a towed array) of microphones (i.e., transducers), and perform algorithmic beam-forming to narrow down the possible points of origin for the sound.
This seems like a pretty obvious approach, but I haven't noticed anyone proposing it.
Some acoustic expert and hospitality expert should team up to create a hotel and/or spa that can dampen or eliminate the hum in some significant way in order to provide an oasis of relief for those severely affected... either through inverse cancellation waves (as suggested in a comment) or by air/water buffers around the property.
This suggests overlapping interference patterns from multiple sources
or multiple sound pathways. Is that a reasonable idea for infra-sound?
I'm looking to make one of these out of bamboo.