As one who can hear these sounds, I can attest to how maddening it is. It's even worse when (most of) the people around you can't hear it, and they don't believe you.
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.
I was plagued by the Hum for years. At times it became astonishingly loud. But I was able (eventually) to figure it out.
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.
This reminds me of the story of how composer John Cage was inspired to write his piece 4′33″ [1]:
'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 did read about those, a "challenge" is how long you can stay in there before going mad - I think the longest one lasted for 45 minutes.
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.
I had very bad tinnitus in my right ear for a few weeks that seriously fucked with my life, and turned out--thank God--to be a sinus issue. A doctor prescribed me a nasal spray and over-the-counter sinus pills, and it started slowly getting better after a few days. I only notice it if I'm looking for it now.
That page right there is why I never used Reddit and when I drop by I just don't understand it. So, your comment sounds interesting, I click the page and it's just a bunch of unrelated stuff with title's like "Does anybody else use it when they don't want to hear something ?" Hear what? What is the level above, what connects these posts?? The top of the page just says "Come for the cats stay for the something" and the top post says "Awesome new relevant CSS trick added to the subreddit." -- What?? the link I clicked suggests something about "earrumblersassemble". Clicking on a Reddit link is almost always a maddening experience for me. What is wrong with me?!
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".
Don't worry, I'm with you on this one. It's a garbage format, and it's assuredly a willful lack of organization as an exclusionary tactic, used to alienate people on some level, and require degrees of subordination among those late to the party. Is it simply a natural defense mechanism, that preserves an otherwise autonomous complex system? Maybe...
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...
Even reddit has its moments. For that matter, so do even YouTube comments.
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
That got me thinking: what if the hum is a two-part process? First, infrasound/near-DC pressure fluctuation triggers the tensor tympani reflex. Then, in susceptible individuals, the tensor muscle twitches, spasms, or otherwise locks up.
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.
> A subreddit for those who can control their Tensor Tympani muscle.
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 don't know the correct terms here, but there is a path from your throat to your ears that is normally closed. When you swallow or yawn the paths usually open, but some people can voluntarily open them.
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 have been working on a project to use some DIY bone conduction "headphones" to do directed noise canceling because I'm on the autistic spectrum and loud places bug the shit out of me and make it so i can't focus. Bone conduction is neat because it works inside your head and doesn't cover your ears. I think BC noise canceling is really under explored for audio related stress issues.
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.
Are you eventually going for an external "headphone" system, a transdermal solution, or actual implants similar to BAHA hearing aids or the DIY transducer implants some of the grinder community have installed, or perhaps even piercings in the tragus?
I have no interest or ability to build surgical implants. Purely over you skin. I've read about people with hearing damage loving bone conduction over regular headphones. It's been described as miraculous by some. Obviously hearing loss is complex and that's not for everyone.
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.
Can you point me at information about these subdermal transducers you're looking at installing in your head? That sounds insane, but I kind of want some.
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 targus and the temple are totally mid and high range. Try putting a 20W amped transducer on your jaw below your earlobe. You get VERY immersive sound. I see no way the targus implant could be worth it. I also don't see a way to put an implant on the jaw that would work because it's moving.
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!
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.
Thanks! I don't get to work on it as much as I'd like but I literally fantasize about it existing every day. Just being able to turn stuff down as needed. Sheesh.
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[1] and so did another company I've never heard of[2]. Also in 2002 the us government funded a $100,000 research grant for it[3]. 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.
edit:
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.
I wouldn't recommend the Earthworks M50 for this application. Earthworks' design approach for these microphones is to maximize time domain performance by having excessive bandwidth, minimal phase distortion, and flat frequency response. In order to achieve this, they have to use a tiny condenser element, which has relatively low sensitivity and thus relatively high noise.
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.
Since you seem fairly knowledgeable about this subject, perhaps you could answer a related question I've been wondering: Would an effective low-cost way of measuring low frequencies (let's say ~20hz) be to use a subwoofer speaker (used as a microphone) hooked up to something that would amplify and recording of the signal? My reasoning is that they're naturally designed to work with low frequencies to begin with (more so than a typical microphone anyway). I would also reason that you could also do a frequency response test over a range of known frequencies and power levels for the specific subwoofer to begin with, and then write a specific software filter to normalize whatever you record from it to get the 'true' sound. Does that make sense?
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.
You're right that you can use a speaker as a microphone, because they're pretty much dynamic microphones run in reverse. However, speakers are exceptionally low sensitivity when used as microphones. You could amplify them and get a usable signal level out of them, but the noise would probably be much worse than a purpose built microphone.
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[1], 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.
Cool, thank you for the link. To measure and correct for the frequency response of the microphone, can't you just play a range of known frequencies that each have known power levels, and then measure the gain/loss in power level that gets recorded by the mic, and then solve for a filter that gives you unity gain on the mic? I assume that you'd have peaks in the frequency response around the natural resonance and harmonics of the mic, and you'd basically just be adjusting for those.
That's how the process works, but it's more complicated than you'd think. The room a speaker is in changes the overall frequency response. Speakers aren't flat, either. There are ways to get past these obstacles, but it can be difficult and expensive to get right. Going to the the world of infrasound just increases the complexity.
Yes, sub-woofer loudspeakers make excellent low-frequency microphones when used with a suitable pre-Amp. And using a PC with Spectrogram software is a great way to record and visualise the sounds.
However, please read my post above on what I actually found.
You could start with two mics going into the same computer. Even a few feet of separation might be sufficient. Plug them into a mixer, one as the left channel and the other as the right channel of a stereo stream to keep their samples synchronized. Filter, then cross correlate the signals to find the phase difference/TDOA.
Since low frequency waves have a very long period, I don't think any mics near each other would give much useful location info. Depending on where a given mic was relative to the wave, I expect the recorded volume would be very different.
Yeah, 20 Hz = 17 m wavelength, so move the microphones to be at least 17 meters apart, or a bit more if you think the sound is below 20 Hz, which should be doable.
And yes, I don't expect comparing amplitude to be useful--sound localization almost always uses TDOA/phase difference for that reason.
All of these that I checked are either obviously fake or have simple explanations. One is a sound familiar to anyone who's played around with a cheap microphone, for example. Some are simple waves anyone can generate.
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.
some are fake for sure. but this is more akin to the likes of strange occurrences of sinkholes than ufos. its not just one person reporting it, but an entire neighborhood.
I don't doubt that some people experience hard to explain sounds. I do doubt that any of the sensational headlines in those videos were written by people who were prepared to consider reasonable explanations. Unfortunately, they were the only people there to look down/around to see if something obvious was making the sound instead of some ethereal oscillator.
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.
I was getting ready to post this. The empirical equation for the frequency of the oscillation is on Wikipedia, which should allow easy testing of the hypothesis that a Karman vortex street is responsible if any particular object is thought responsible. As I recall, if the Reynolds number is too high, the oscillation will become broadband, so it won't sound as described.
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...
Why would a humming noise make people go crazy and leave their tents naked, cause a skull fracture and two chest fractures, remove one's eyes and tongue, etc.?
Infrasound can cause weird psychological effects. Fractured bones can be caused by carelessly scrambling over uneven terrain which the campers may have done in terror. Vortex streets can also supposedly be composed of large vortices which are like tornadoes. Maybe the fractured bones could be explained by this as well. Missing eyes and tongues can be caused by wildlife.
I'm confused. The attached NY Times video clip has a very audible and noticeable hum and throb – it can't be just infrasound. Is that the actual hum people are hearing/not hearing? Or is it an attempt to reproduce it, perhaps?
I was looking for that too; indications in the article that people actually recorded and had waves/evidence of the hum. It's impossible to tell if the noise in the video is just stock sounds or an actual recording of the event in question.
That's funny, when I moved to Colorado was the first time I started hearing it. My wife can't hear it at all but it's so loud sometimes at night it drives me crazy. It's not in my head, it's definitely coming from a certain direction. Its very low, I can barely see it on an app I put on my phone, "Spectroid". I'm pretty sure I know what it is, the coal trains moving down the front range. The tracks are like 10 miles away but the sound is so big and low that when the weather is right it propagates for miles. If I can hear it while the train is on a 20 mile stretch of track then a new train will come before the previous fades. I'd wager that distant freight trains and a gentle breeze cause this noise for a lot of people.
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.
If I open the front window and back window in my car then drive at a specific speed I get a very weird woop-woop-woop and it feels like the air is pushing me back and forth in my seat. It pulses my head.
My car does this too. No previous car I've owned has had the same issue. Hopefully it isn't inherent to modern automobile aerodynamics because I'd like my next car to be one without it.
For low frequency stuff, I would suggest using an accelerometer instead of conventional audio equipment. A small one could also be placed on a large diaphragm to allow more movement at really low frequencies.
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.
I can hear these sounds too. Earplugs definitely make it worse. I grew up in a small town right next to a huge military base and aircraft flyovers were a very frequent occurrence. To me the sound sort of reminds me of a really faint helicopter or really faint jet engine in the distance, just on the edge of hearing.
A few years ago they drilled for gas a few kilometers outside the city (about 3 km from my house) — this caused a faint humming noise that seemed to come from everywhere but nowhere in particular. Stand still in a room, hear the noise. Lie down, cover your ears, hear the noise. Put earplugs in, hear the noise. Hugely annoying if you're the kind of person that doesn't sleep well with such nuisances.
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.
> 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.
> Meaning it's just a rendition of a hum, not an actual recording of "the hum".
...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...
There is nothing to insulate against these large, low frequency waves. They penetrate solid rock. Perhaps enough water could absorb the waves and dissipate them, but that's not really an option.
When doing laser holography the standard practice is to build a large, heavy bed, like a sturdy wooden frame filled with dry sand, and lay that on top of something that absorbs vibrations like a series of tires and inner tubes.
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.
This is only effective if the microphone and speakers (inverse wave) are where you are... such as on your head. And it depends on the microphone's ability to detect VLF. Even then, the speakers probably don't do well generating 20Hz or lower.
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.
Sigh. I've coded too much this week. My brain just immediately went to: comment out half the city at a time and binary search the source. Guess you can't really do that.
I wonder if the hum persists during a power outage.
"The University of Windsor report said the hum’s likely source was blast furnace operations on Zug Island" ... which is over the border in the United States.
Cutting off the power to that island would be a good thing to try, but apparently the US is uncooperative.
I'd guess amplitude is massively affected by microphone sensitivity. This is not easy to measure and might depend on the direction.
Consider:
* 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.
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[1] using an RTL-SDR, or a cellular signal, or GPS, or maybe using NTP?
Yes, that seems like the best approach. At 20Hz waves, ntp would probably be good enough.
The real issue I can see is to get that time-data into the sound data.
Maybe you could time-stamp the beginning of a recording, and start a new recording every minute (to compensate clock drift).
That might work, biggest issue I see is potential variable latency between 'starting a recording' and the actual first recording happening.
We can put Hamburg (Germany) on the list of "humming cities" too. When I moved close to the harbour I started hearing a humming sound, espececially at night, almost exclusively indoors.
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.
Is a hum not more or less expected in the vicinity of busy harbors, even more so than in general industrial areas? Harbors attract a lot of possible sources that could cause a hum: maritime equipment, ship engines, generators, industrial equipment, large refrigerators (in containers or in warehouses), ...
You may want to read about the Kokomo, IN "hum" investigation which was traced back to an industrial source [1].
> Is a hum not more or less expected in the vicinity of busy harbors, even more so than in general industrial areas?
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 take prescription stimulants for APD, audio processing disorder; whatever that actually is.. For me, I have difficulty hearing people talk and focusing when exposed to multiple or dynamic background noises.. Basically it's a failure of autonomous filtering or prioritizing of sounds.
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..
Were there any ships around? Last year I had vacation in Malta and I could barely sleep due to constant, low, barely noticeable noise. I have attributed it to the ship engines, as there were many of them around and couldn't find better explanation (tried to turn off every appliance and sleep in different room with no avail).
I'm listening to this right now [1] and (for those of you who don't have a chance to hear it right now) it definitely isn't what I would call a "hum"... that's way too gentle and not bass enough to describe this sound. I'd call it more like low-frequency rumbling (though that's probably not a perfect word for it either).
So today I learned I’m sensitive to sounds like this. I’ve been hearing stuff like this my whole life when nobody else could. Sometimes I get high pitched noise too. I just thought it was me.
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.
It's actually a not unpleasant brown noise-like sound. At least that's how it comes out of my hifi. Over bluetooth and after YouTube compression so perhaps high fidelity isn't the right term.
I'm not sure... for me the unfiltered version was annoying but bearable for a bit... but I could see getting driven mad by it after a while. The filtered version was so bad that it almost made me wonder if I'm going to damage my ears, so I stopped listening to it halfway. I was using decent BT headphones so I'm not sure if that makes any difference... it may depend on how decent your speakers are at playing 30-40 Hz.
(Side note: Does BT audio do some kind of lossy compression? Why is it relevant that you mentioned it here?)
“Does BT audio do some kind of lossy compression?”
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.
Exactly, BT audio uses lossy compression. There are several codecs available but I'm on Linux and the receiver is pretty old so it's probably the weakest of them: SBC.
The filtered sound is pretty bad, yes, dread inducing.
Update: For what it's worth, I just tried it with wired headphones (again, a decent pair) and they don't sound different as far as I can tell, so BT compression doesn't seem to be having any observable effects.
Listened to the recording (via Bluetooth) on headphones known for their good reproduction of low hertz sound, and the original recording was downright uncomfortable for even a few seconds
I'm wearing over-ear monitors and the rumble is very slightly unsettling in an uncanny way. And that's with all the highpass of the recording. Real life has all that sub 20 Hz that most mics can't pick up. I can see how this could easily drive someone bonkers
As a kid I remember going past the area around Zug Island on a boat.
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 [1][2]. 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.
We had a "hum" sound in cambridge MA. Its one of those sounds when you walk through you don't think anything of it, but if you live near it.... (I was one of the lucky as I couldn't hear it from my bedroom). Incredibly hard to track down, it was determined to be Fans on top of a building. And it was fixed.
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.
We had a similar issue at an apartment block in Australia. The most amusing sight was a bunch of residents, all wandering the corridors trying to find which room was the source, but as in your case it was fans on the roof.
I'm not sure it's related to these humming reports but there is a lot more ambient noise than most people appreciate.
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.
Would "the hum" not be noticed in a lot more areas if it were caused by 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.
> Would "the hum" not be noticed in a lot more areas if it were caused by jet engines?
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.
Three people so far have suggested in the comments here it should be "easy" to triangulate it. Note that according to Zug Island's Wikipedia page, "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" and that "the City Council had already spent over $1 million to help Windsor and Ontario find the source of the noise".
I think there's a bit of armchairing going on here, in that people are definitely trying the obvious already.
No tinfoil hat needed. It is very possible for some machine at the steel factory to have foundations in a slab of deeper bedrock that becomes more shallow where the noise is more prevalent. The noise would just come from 'everywhere'
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.
It's relatively trivial to find direction of the 30 Hz sound source, given 1 million budget - you just need to place microphones 11 meters apart and raise them above buildings until you get direct line of sight to the main source.
A square block? 5-10 microphones is plenty. Your goal is to find a direction from the place you deploy, not to blanket the city. Then you can redeploy somewhere else to get another direction, etc.
"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."
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"?
I went to school and worked for a while studying spectrum management. It boggles my mind to this day that drones get in the way of fire fighting and emergency services because an obvious first step world be to allow emergency vehicles & helicopters to jam the frequencies of drones. There are plenty of other vehicles with this ability (military, secret service, etc) so it's not like the technology to solve the problem is unobtainable or non existent.
Would that be legal? Does the FCC offer such an exemption to laws prohibiting signal interference? And in what capacity? We've seen law enforcement jam cellular networks, but firefighters and EMTs? Helicopters? Should civilian helicopters also be able to jam signals? Would all this signal jamming (mostly of Wi-Fi bands) interfere with emergency services equipment or the ability of victims to call for help?
The problem is that there's an infinite number of possible frequencies. Most Hobby drones use one of the ISM "junk" bands (eg 900MHz, 2.4Ghz, etc), but it's impossible to jam ALL of the possible frequencies without wiping out communications over a wide area.
Jamming equipment is heavy, bulky, expensive, maintenance intensive, and especially power hungry. Plus due to the vagaries of signal propagation the effects are somewhat unpredictable. Installing jammers on civilian helicopters would be totally impractical.
"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."
"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.
Yes there is. At least with frequency assignment. There are very strict policies that any frequency usage within 50 miles of an international border must be approved by the appropriate authority on both sides. The rules may not apply to non-communication based sound (which is an obvious failure), but it's not like there is no framework for this kind of thing, it just doesn't extend far enough.
typical triangulation would depend on the sound being heterogeneous in waveform/volume right? If it's a constant hum then you'd only have volume dissipate as you move away which would get a lot harder as sound has different loss functions as it moves through different materials.
No, the triangulation you would use for a project like this would look for time delay or phase lag between 2 (or more) adjacent microphones.
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.
What I don't understand is if they are just trying to locate sound source or looking for other waves, such as electromagnetic ones. When I walk under high voltage trellises I always hear my head humming.
You don't 'hear' EM waves. What you're hearing near high voltage lines is coronal discharges near the conductors; The field strength is high enough to ionize the air around the conductor causing it to move around, moving air = sound.
I don't buy it at all. The article takes a very strangely sympathetic tone toward the whole 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.
It's complicated by the fact that United States Steel is in the US, whereas Windsor is in Canada. It's not just a local government issue, it's an international issue.
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.
I find that it's easier to tune out something that is totally periodic and unvarying. As annoying as a smoke detector chirp would be, your brain knows with certainty the timing and sound of it and can process it out completely. A noise that is generally around, but comes and goes and varies in pitch and volume without predictability, can be much more annoying.
My experience is that it’s pretty damn hard. SOMETHING is generating a low frequency hum that I can hear in my bedroom in Seattle; in fact I’m in there’s hearing it right now. It’s been going since somewhere last summer. I hear it every night and it’s still maddening.
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!
When I first moved to Seattle I lived in an apartment in Kirkland and suddenly the hum started. It lasted for months until I moved out and it almost drove me nuts. It was as if it was drilling into my brain at night. Oddly, my wife didn't hear it.
... fascinating. There's no way that's easier than replacing the battery or even the detector itself. Why suffer through something so trivially fixable?
> Why suffer through something so trivially fixable?
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.
With you on the laptop thing, I'm 90-ish kilos and with a good backpack I wouldn't care if it was 2Kg or 6kg, between all the other stuff in there the laptop often isn't the heaviest thing in there.
It's only suffering if you're aware of it. We've gone months with several chirping at the same time (due to a different wiring issue) and they are incredibly easy to forget about. We'd only remember when talking on the phone and the other person would ask about the noises.
Well damn ... Punishment for my ancestors stealing their land and whatnot ... seems fair through that lens ... should make my decent into madness a tad more comforting
Has there been an attempt to trilaterate/triangulate the sound? Should be fairly simple to rig up several recording devices in sync around, and use timing/loudness to get an idea of origin, despite the large wavelength.
According to Wikipedia, that is definitely the source of the him:
Noise and vibration[edit]
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.[3][4][5]
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.[6]
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.[7]
Another report released on May 23, 2014, confirmed that Zug Island was the source of the hum.[8][9]
[3] Schmidt, Doug (September 21, 2011). "Zug Island likely culprit of Windsor hum". The Windsor Star. Postmedia Network Inc.
[4] "Mysterious noise escalates in Windsor, Ontario". CBC News. January 30, 2012
[5] Ashifa Kassam (June 7, 2016). "The 'Windsor Hum': where is the noise plaguing a city of 210,000 coming from? | World news | The Guardian"
[6] "River Rouge calls off search for Windsor Hum". CBC News. November 7, 2011
[7] Tingley, Kim (June 24, 2013). "The Sound and the Fury". OnEarth.org. NRDC
[8] "Mysterious Windsor Hum traced to Zug Island, Mich". CBC News. May 23, 2014
[9] Colin Novak (May 23, 2014). "Summary of the ‘Windsor Hum Study’ Results"
In a place like that, there would likely be multiple sources. Such as the three blast furnaces there. Which are among the largest in the world. They blow lots of hot air through lots of extremely hot iron ore, coke and limestone.
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.
uuhhh..."Originally a marsh-filled peninsula at the mouth of the River Rouge, it served as an uninhabited Native American burial ground for thousands of years."
Now I am deeply curious! I’m a Detroiter and Zug Island is a quick drive south. Is it audible from the US side? I have a passport, but “I want to hear the Windsor hum” might not, unfortunately, fly at the border anymore.
Now I am curious: do you really need to state a reason to pass a border? In Europe, when you don't need a visa, you simply cross the border, no questions asked.
And if somebody asked me anyway, I'd just say "I want to visit the town. I'm curious."
Welcome to the lovely United States. ;) Since 9-11, border security, especially returning to the US, has gotten extremely paranoid. At all three spots between Michigan and Canada (the Ambassador Bridge, the tunnel, and the crossing in Sarnia), everyone is stopped and questioned by border agents if they don’t have some kind of automatic pass that requires clearance ahead of time. You’re asked a lot of questions, like where you’re going, whom you expect to see, how much money you have, how long you expect to be there (in Canada; probably similar for visiting the US), etc. Going into Canada seems to be easier, although it really depends on how that border agent is feeling that day. All of my times so far have been relatively painless: “Why are you visiting?” <I state reason> “Oh, okay. Enjoy Canada!” It’s a crapshoot. Sometimes they search your car.
I have to say, I do miss the Schengen area. Going from the Netherlands to Germany was a breeze.
It seems like a sensor array across the city of just a few sensors could help detect the source. Using microsecond differences in the arrival of the sound, you could at least tell what direction it is coming from.
You'd have to be able to synchronize the phase of your sensors. If it's a low 30hz hum with very little differentiation between individual cycles you might not have an easy way to do that. You could possibly build a big array with microphones at < 1 wavelength apart so you can observe the waves passing through, dunno.
Also the sound could be reflecting downward from cloud/temp layers, greatly complicating it.
I witnessed something similar some years ago, in Lisbon.
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.
Out of interest, how do we know it's not a common but undocumented form of tinnitus? Perhaps one that is more likely to present in certain weather conditions, so people's complaints will correlate?
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!
> Out of interest, how do we know it's not a common but undocumented form of tinnitus?
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.
Sound is such a context-dependent experience. I vividly remember taking a walk with my parents in the Alps through the most pristine landscape. It was beautiful, except for the annoying sounds of a nearby highway. A few minutes later, we expected to see that highway across one hill, but were astonished to find a glorious waterfall. The instant we saw the water, the experience of the sound was transformed to something entirely beautiful.
The similar experience but with taste, or the tactile sensations of food, is even worse for me. I've never noticed this with sound that I can remember.
A few years ago there was reportedly a persistent hum where I live in Surbiton, Surrey, UK. There was a thread on a residents message board[0] that escalated only as far as the local rag, and the council issuing noise diaries[1]. What disappointed me the most is that despite living in almost the epicentre of where the complaints were made, I never heard a damn thing.
Seismologists now have some tricks for locating hum sources. Standard earthquakes have an impulsive start. So with four or more seismograms you can triangulate for the unknowns x, y, z and t0. Hum noises dont have an definitive starting time. But a version of seismology called inferometry can find the origin. You basically cross correlate all pairs of seismograms with signals. The peak lags define a hyperbolic wavefront you can invert for the origin.
This method has been used to find submarines. To look volcanic tremors which have now clear start. And Earth hum which often seems associated with large oceanic storms.
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).
I lived through this when i went to the University of Windsor, it's hard to describe to people it doesn't bother. The hum would keep me up and my girlfriend at the time almost never noticed. It was like being at a loud concert where you can feel the vibrations in your chest.
Did everybody get a takeaway shop's fan duct stuck to their wall like at my last rented flat?
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 used to live close to a factory district here in Brisbane which had a persisting hum. One night, I apparently half woke up, swore, put on underpants and rode out on my bike to find it. I remember coming back to bed, I don't remember what drove me to try and track this stuff down. I kind of wish I had found it because having a guy in his jocks knock on the factory door at 3am shouting about the noise would have been good free entertainment.
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.
To those who are affected by the incessant hum, have you ever tried to actually measure it by some technical equipment? I am pretty sure there are devices that can detect and register sounds of almost all frequency levels.
What about the noise canceling headphones? Sony, Bose and Sennheiser have some top-notch headphones that cancel out static noise. Being very sensitive to noise, I use one of those and am totally satisfied.
From my time working for the U.S. Navy, I find this very reminiscent of the problem of finding a submerged submarine at a distance, based on its low-frequency sound emissions.
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.
I didn't mean to imply that it's a good technique for pinning down a particular building or even block of the city, but the technique would work (I imagine) for large-scale localization of the sound source.
Is it wrong to suggest this as an opportunity for a business?
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.
Well I found this video by vice https://www.youtube.com/watch?v=jhXaM_r80_c which claims that they found the source in zug island across the river, but were not allowed to investigate further due to cross-border politics.
> The Hum is a phenomenon, or collection of phenomena, involving widespread reports of a persistent and invasive low-frequency humming, rumbling, or droning noise not audible to all people.
“It’s as if you had a fire hose moving back and forth and the people who have the water falling on them hear the noise, and if you’re outside that stream, you don’t hear the noise,”
This suggests overlapping interference patterns from multiple sources
or multiple sound pathways. Is that a reasonable idea for infra-sound?
Could an algorithm, like the one used in shazam, be fed a sample set of noises from many different machines/industrial equipment so that we could hopefully be able to take the noises/sound profiles of the things being posted in the comments here and check to see what the most likely source is.
Has constructive interference of multiple low frequency sound sources been considered? It could be that they are all undetectable on their own but cause localized areas to have a much higher amplitude sound? I guess reflections of the sounds in the right areas could have a similar effect?
These persistent sounds may make you go crazy for sure. For a a few weeks a few years back I could hear sound of my blood flowing through my head. That was not funny to say the least. Fortunately, it went away by itself.
Brainfart ahead: The way the united states are out of hand lately would kind of get me to no longer rule out the possibility that they might be drilling across the border for whatever they might find?
This has been going on for a lot longer than the current US government. Chances are high it's just Zug Island, which contains blasting furnaces for steel and whatnot. The problem is that Zug Island is a part of Michigan, while Windsor is a Canadian city, so investigation is pretty difficult.
Common causes of such hums: sewage pumps, large transformer stations, roof mounted AC heat rejectors, hydropower plants, refrigeration installations. It's surprising how far contact sound will carry.
I built a laser once. Based on the crappy efficiency my conclusion would be that the chances of this happening are very low, especially in quantity, even without accurate data.
We had a hum in Calgary Alberta. It became the subject of an ongoing project in our embedded systems engineering course to identify and triangulate the sound.
Install time-synchronized sound detectors/recorders in decent distance from each other and measure intensity and propagation of sound spike across time.
Correlate data.
This should provide information about the direction of source.
Further tests in the direction of source would eventually solve the mistery.
Of course "secretive" industrial facilities would likely be the culprit.
@dang why did you delete the "And no one knows why" from the title? Did it sound clickbaity to you? Seems pretty critical to the article to me. The whole thing is about the search for what the hum is, not what the hum is.
It's a debatable one in this case IMO. "There's a Persistent Hum in Windsor, Ontario, and No One Knows Why" tells me what I need to know -- it's a mysterious hum akin to what I've read about many times, so there's little need to click. "There's a Persistent Hum in Windsor, Ontario" suggests it may be an article about a known cause/why there is a persistent hum, inducing me to click to find out the reason.
A better solution might be to rephrase (e.g. "There's a Persistent Hum of Undetermined Origin in Windsor, Ontario") to avoid the clickbaity style phrasing, rather than just deleting the clause outright, but then you start editorialising which brings its own set of problems.
jet cooling of upper atmosphere forcing chemtrailed metallic clouds, metallic train smoke, and metallic boat fog to the ground to mix in with power pole add-ons. wake up and smell the metal.
Sorry for this I am not experiencing it so maybe I'm completely wrong but these people seem to be overblowing this a lot. Health effects? I mean, it's a hum. Sure you can't find the source but heaters hum, ACs hum, cars going past hum, bass hums. Like how is it possible that it's this huge of a problem? When a humming stops I tend to actually miss it because it becomes too quiet. I tend to hear the air conditioners or heaters at work all day every day for at least 8 hours. Is this hum much much louder than that or what?
Speaking personally, noises that I can locate the source/direction of are easily ignored. Noises that sound the same in multiple locations/appear to be coming from everywhere are _much_ more annoying (I once had a fridge that produced a whine that was right of the cusp of my hearing -- both in volume and frequency -- and I must have spent a good 20 minutes tracking it down because it was impossible to ignore - it sounded the same from anywhere in the room until I got within a few inches of the source). If it's a noise similar to that, I can see it potentially effecting people's sleep and having knock-on health effect.
If it was louder, some may actually find it easier to ignore. I can sleep easily with either a quiet room or with a loud room fan on, but if there's just the fan noise from my NAS I find it much more difficult.
Good for you, but for some of us it will drive you nuts. The quieter it gets as you try to sleep, the louder the hum seems to get. And if you hear it more in one ear than the other, it feels like your head is warping from more pressure on one side than the other. Sure it's "all in your head", and just like with being a little too cold you could theoretically train yourself to ignore it. But that's easier said than done.
Garbage, sensationalist title with mentions of "unknown origin". Even the article says the likely source is Zug island, but of course this wouldn't get as many clicks.
According to the mentioned University of Windsor report (http://www.international.gc.ca/department-ministere/windsor_...) "A previous study confirmed the existence of the low frequency excitation and estimated the source to be in the vicinity of Zug Island". If this article was written with the assumption that the source is likely known, it would have been a reasonable read. Instead, it should have focused on getting the city to do something about it, by approaching the property with a noise complaint warrant, discovering the source, fining those responsible, and changing policy if needed to solve it. If all of the above is impossible for whatever reason, why doesn't the article mention the reasons instead of making it the issue seem like sensasionalist "mystery" news.
Findings from your link, seems you didn't read it.
Number 1 "We do not find common signals at both arrays which could plausibly be associated with the Hum. We are unable to geolocate a definite source for the Hum using common cross-bearings."
Number 5 "The bulk of our observations from both stations do not support the hypothesis that the source of the Hum emanates from Zug Island"
> We note that the bearing from Array 1 to the most probable source of the Hum points well to the South of Zug Island. The bulk of our observations from both stations do not support the hypothesis that the source of the Hum emanates from Zug Island.
Even if it is from Zug Island, "unknown origin" is still appropriate until they know WHAT is causing it.
They have it narrowed down to a few thousand feet. To call it "unknown" is just unfair. They might not know which steel plant is producing it, but they can narrow it down to a small handful, far from "unknown". They have enough evidence of which company is producing the sound (United States Steel), so the only thing stopping them from getting police or lawmakers involved is the fact that no one on the US side cares enough. The article could have mentioned this caveat, but after the couple sentences about the likely cause, it's followed by more "It’s like chasing a ghost" rhetoric.
It's constrained, but it's still unknown. It's not saying there is no clue about the origin, and narrowing it to a few thousand feet/a few possibilities still means the source is unknown.
Different case IMO. There you know both the object and the location to some margin of error. If there was a strange noise in the room, you might know the location to the same degree of precision (i.e. it's somewhere in the room), but until you determine the object making it, the source of the noise is still unknown.
Yes, that's my point. This would be an interesting article if it explored the possibilities and difficulties in solving the problem due to the national border instead of just throwing up its hands and saying "It’s possible that no matter what is done to relieve or attenuate the noise, it might never be enough".
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″.'
[1] https://en.wikipedia.org/wiki/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.
[1] https://www.youtube.com/watch?v=mXVGIb3bzHI
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.
https://en.wikipedia.org/wiki/Grinder_(biohacking)
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.
https://www.digikey.com/en/product-highlight/p/pui-audio/aud...
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.
http://www.st.com/content/st_com/en/products/evaluation-tool...
https://stm32f4-discovery.net/2014/10/stm32f4-fft-example/
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[1] and so did another company I've never heard of[2]. Also in 2002 the us government funded a $100,000 research grant for it[3]. 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.
[1] http://appleinsider.com/articles/15/08/27/apple-researching-...
[2] https://patents.google.com/patent/US20150170633
[3] https://www.sbir.gov/sbirsearch/detail/306044
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.
edit: 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[1], 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.
[1] http://volcanomodels.sr.unh.edu/jbj/MICROPHONES/microphone_l...
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.
https://en.wikipedia.org/wiki/K%C3%A1rm%C3%A1n_vortex_street
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.
https://journals.ametsoc.org/doi/abs/10.1175/1520-0450%28197...
Wonder if it is something similar.
https://blog.caranddriver.com/explained-that-weird-throbbing...
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?
Audio insulation?
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.
https://www.google.com/search?q=anechoic+chamber&tbm=isch
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.
Consider:
* 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[1] using an RTL-SDR, or a cellular signal, or GPS, or maybe using NTP?
[1]: https://www.nist.gov/pml/time-and-frequency-division/nist-ra...
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 [1].
[1] http://www.le-bruit.com/easy-media/kokomo_hum_report.pdf
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.).
Example: http://www.sueddeutsche.de/muenchen/ebersberg/steinhoering-l...
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..
[1] https://www.youtube.com/watch?v=tPDILKQjJW8
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 [1][2]. 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?
[1] https://www.flickr.com/photos/gsgeorge/3705474769
[2] http://rebelmetropolis.org/a-hellscape-among-the-ruins-zug-i...
- https://smile.amazon.com/Blast-Furnaces-Bernd-Becher/dp/0262...
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.
https://www.forbes.com/sites/alexknapp/2013/06/28/shotspotte...
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.
Another problem:
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.
0. http://knkx.org/post/mysterious-hum-keeping-west-seattle-nig...
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.
https://en.wikipedia.org/wiki/Zug_Island#Noise_and_vibration
> it served as an uninhabited Native American burial ground for thousands of years
http://www.international.gc.ca/department-ministere/windsor_...
> 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[edit] 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.[3][4][5]
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.[6]
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.[7]
Another report released on May 23, 2014, confirmed that Zug Island was the source of the hum.[8][9]
[3] Schmidt, Doug (September 21, 2011). "Zug Island likely culprit of Windsor hum". The Windsor Star. Postmedia Network Inc. [4] "Mysterious noise escalates in Windsor, Ontario". CBC News. January 30, 2012 [5] Ashifa Kassam (June 7, 2016). "The 'Windsor Hum': where is the noise plaguing a city of 210,000 coming from? | World news | The Guardian" [6] "River Rouge calls off search for Windsor Hum". CBC News. November 7, 2011 [7] Tingley, Kim (June 24, 2013). "The Sound and the Fury". OnEarth.org. NRDC [8] "Mysterious Windsor Hum traced to Zug Island, Mich". CBC News. May 23, 2014 [9] 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.
http://www.thehum.info
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.
https://www.20k.org/episodes/mystery
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.
https://en.wikipedia.org/wiki/The_Hum
It could even be causing the bones in their heads to resonate, like how those kids toothbrushes that make you hear music[1] work.
That would explain the difficulty in locating the source.
[1] https://en.m.wikipedia.org/wiki/Tooth_Tunes
[0] https://surbiton.com/forum/surbiton-background-hummmmmmmm [1] http://www.yourlocalguardian.co.uk/news/10999038.Mysterious_...
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.
Transcript: https://www.stuffyoushouldknow.com/podcasts/how-the-hum-work...
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.
[1] https://news.vice.com/article/a-mysterious-hum-is-plaguing-w...
[2] https://www.youtube.com/watch?v=jhXaM_r80_c
https://en.wikipedia.org/wiki/The_Hum
This suggests overlapping interference patterns from multiple sources or multiple sound pathways. Is that a reasonable idea for infra-sound?
https://www.huffingtonpost.com/2012/09/07/seattle-hum-fish-m...
I'm looking to make one of these out of bamboo.
Undrground activity would have very specific signatures.
http://www.bbc.co.uk/news/magazine-35344544
http://m.newsok.com/article/2875333
This should provide information about the direction of source. Further tests in the direction of source would eventually solve the mistery.
Of course "secretive" industrial facilities would likely be the culprit.
EDIT: Thanks to ocdtrekkie for digging in further on this:
https://news.ycombinator.com/item?id=16424617
http://www.cbc.ca/news/canada/windsor/mysterious-windsor-hum...
https://youtu.be/5WkLoOvm2Yo?t=316
(It's better to send questions like this to hn@ycombinator.com, as the site guidelines ask. When you post in the thread, we only see it by chance.)
A better solution might be to rephrase (e.g. "There's a Persistent Hum of Undetermined Origin in Windsor, Ontario") to avoid the clickbaity style phrasing, rather than just deleting the clause outright, but then you start editorialising which brings its own set of problems.
If it was louder, some may actually find it easier to ignore. I can sleep easily with either a quiet room or with a loud room fan on, but if there's just the fan noise from my NAS I find it much more difficult.
According to the mentioned University of Windsor report (http://www.international.gc.ca/department-ministere/windsor_...) "A previous study confirmed the existence of the low frequency excitation and estimated the source to be in the vicinity of Zug Island". If this article was written with the assumption that the source is likely known, it would have been a reasonable read. Instead, it should have focused on getting the city to do something about it, by approaching the property with a noise complaint warrant, discovering the source, fining those responsible, and changing policy if needed to solve it. If all of the above is impossible for whatever reason, why doesn't the article mention the reasons instead of making it the issue seem like sensasionalist "mystery" news.
Number 1 "We do not find common signals at both arrays which could plausibly be associated with the Hum. We are unable to geolocate a definite source for the Hum using common cross-bearings."
Number 5 "The bulk of our observations from both stations do not support the hypothesis that the source of the Hum emanates from Zug Island"
> We note that the bearing from Array 1 to the most probable source of the Hum points well to the South of Zug Island. The bulk of our observations from both stations do not support the hypothesis that the source of the Hum emanates from Zug Island.
Even if it is from Zug Island, "unknown origin" is still appropriate until they know WHAT is causing it.
I'd say you didn't read the article. They're pretty clear that it's because Zug Island is in the USA while the sound problem affects a city in Canada.