It took me and my neighbours a month to find the source of a hum that was resonating with our windows. It was torture, with midnight walks and lurking around potential sources, mapping nearby industrial sites, and questioning our sanity, while our windows were vibrating without a stop. We were very lucky to track it down to a badly installed air conditioning vent 200 m away.
1. A few years ago I spent some time in Falmouth, MA and there was an ongoing battle over newly installed wind turbines. The humming sound was getting to people, including to the point where they were getting headaches. Some people heard it and others didn't. The locals were going to war with the initiative. This article reminded me of that and I checked in on the ordeal. Looks like they shuttered the project and have started dismantling the turbines. It seems like a total failure: https://www.wsj.com/articles/a-green-new-deal-in-profile-115...
2. I was on a solo canoe trip in a remote part of Maine a couple of weekends ago and I kept hearing the sound of a motor start up and then die down. I heard it multiple times along a 25 or so mile stretch of water with the only other sounds being birds, moose rumbling in the woods, and beavers slapping the water with their tails. I chalked the sound up to some wind turbines I had seen on my drive up there and felt justifiably annoyed at the encroachment of the industrial world into my backwoods trip. I did some research when I got home and it turned out that I was hearing ruffed grouse "drumming" to mark their territory. In retrospect, it's an amazing sound: https://youtu.be/q0obByQW23k?t=21
https://www.quietpc.com/nf-a12x25-5v
https://cougargaming.com/us/products/cooling/cfd_red_led_fan...
I found my trail journal entry about this: https://www.trailjournals.com/journal/entry/14113
Finally, at one point I asked a group of other thru hikers if they had experienced it, and they all excitedly nodded, but none of us knew the source. Finally, some local day hiker said “oh, it’s probably just a grouse”. And the mystery was solved. Many of us were very confused for months!
Surely this was an issue with these specific turbines, right? Not a problem with all of them?
Sure, yes. The annoyance is justifiable. And I do not mean to come off as combative. I just wanted to say that our alternative forms of energy also encroach on the natural world in other ways (climate change, dirty mining, etc). So while turbines might more viscerally feel like an encroachment on nature, we must remember that they may displace some more destructive form of energy generation. I am not equipped to argue definitively that they are better, just that the visibility of wind turbines might influence our perception of them.
Every single time.
Kinda soothing, really. Just soft, deep thumps.
I was never able to identify it, and searching online gave me nothing.
It’s always the same length, about a second. It’ll come in pulses of 2 or 3 usually. Spread out a few minutes a part. It definitely sounds like an electronic sound. Almost like a sci fi satellite sound but deep in the water far away. Or maybe a far away whale mourning or something.
I just traveled for 3 months and heard it spread across 10 cities.
It’s very weird...
Any idea what you'd use to track down very low frequency noise sources(i.e. 15-60Hz)? I don't think a lot of sensors do well in that range.
I checked everything, but nothing. Asked my grandparents about it, but they couldn't hear any noises. Finally I got a friend over, and he could hear it clear as day.
One day I noticed my grandmothers hearing aids lying in a casing, and it turns out those were the source of noise. She'd forget to take out the batteries, and they would create a negative feedback-loop that came and went.
It's why kids could hear the whine of CRTs and their parents were completely oblivious, etc.
I feel like I wasted a bunch of perfectly good political capital at work in my fight with building management to get them to fix the lights. They finally replaced them with ballast-free LEDs after six months.
Could also be electronic noise. I wonder what the machine is.
The local council didn’t really care when I told them. It doesn’t bother me too much because I get up quite early anyhow, but I imagine this truck would manage to bother a rather large number of people every week. I wonder if the sound will go away next time it’s serviced.
I tried using baudline[1] (a 20-year-old program!) but it didn't work out-of-the-box on my current Linux installation. Instead I found something called Sonic Visualizer[2], which, while not real-time, worked out of the box. Using Pulse Audio 'pavucontrol' it was easy to configure Sonic Visualizer to use as its input the 'monitor' channel, i.e. capturing the audio while the video played on Twitter.
I'd love to get baudline working again since it's able to run in realtime.
It looks like the main tone is at 440 Hz and tones at 400 and 480 Hz come and go. Not sure what to conclude from this. :-)
The largest tuning fork in the world! [1]
What errors are you getting? You're right it doesn't work OOTB, I needed to fiddle with it a bit.
UPDATE: The sound is intentional. Or, at least, known about in advance.
According to a statement Saturday morning by Paolo Cosulich-Schwartz of the Bridge District, "The Golden Gate Bridge has started to sing. The new musical tones coming from the bridge are a known and inevitable phenomenon that stem from our wind retrofit during very high winds." Cosulich-Schwartz adds: "As part of the design process, the District did extensive studies on the impacts of the project, including wind tunnel testing of a scale model of the Golden Gate Bridge under high winds." Those tests, seen in a video here, showed that the bridge "would begin to hum" when air passed through it more freely.
Thank you for sharing.
https://en.wikipedia.org/wiki/Aeolian_harp
https://www.youtube.com/watch?v=CtzSm76ppS4
They are pretty cool art installations. The Golden Gate bridge may now be the largest such installation ever built!
Yes, it cannot be a 24/7 thing, the harp/bridge is too loud. Also, putting resonances into a suspension bridge is likely to be unsafe.
That said, like the chiming of church bells in a village, it may be used selectively. I can imagine some Burners quickly putting up an adjustable mechanism to have the bridge sing/chime.
Something that can point into the wind correctly (to some degree) and then be readjusted to turn off. Possibly to make more than just one note, like a carillon of bells in a bell tower.
Maybe at the tops of the hour it can turn on/off, like a church bell, to signal the time. Or on special occasions like New Years Eve, the 4th of July, etc. Or for swearings-in of a mayor's term, etc. Heck, even as a warning system for earthquakes.
Having that loud of an instrument, powered by the wind, and then controlled by a few hundred actuators or a bridge-worker/bell-ringer moving steel beams in and out, it's just too good of an idea.
If something like that could be made to work, on such an iconic bridge, well, that's a whole new industry. People have done 'love locks' for years now, chiming bridges would be a great idea too.
If you really want to help build a dystopia, you’d probably have a bright future in advertising. Apparently electric car noises were less about safety than branding.
Some of the car manufacturers wanted their cars to blast sound logos all the time, but they were afraid the first movers would be lined up against the wall and shot.
Electric cars were the perfect excuse to do it anyway and blame regulators, so their lobbyists made it happen in the name of safety.
I can’t believe it’s the bridge.
Spat out my drink at this comment.
To get direction and location, you need acoustic samples from multiple widely-spaced locations, all synchronized. Human ears are not wide enough apart to directionalize low frequencies, but with a baseline of tens or hundreds of meters from separate cell phones, it's not hard. Run a correlator, line up the samples, compute the hyperbolas of constant time offset, (like GPS and LORAN) and find the target.
This needs an app with timing accurate to a millisecond or so. Can you get that from cell phones? The built-in clock synchronization isn't that good. The GPS receiver has more accurate time, but you may not be able to get at that.
A solution like this could resolve many of the lingering "hum" cases. Often they are only heard by a few people, and those in charge of environmental control don't tend to take it seriously because "they don't hear it", or because they or the higher-ups are hiding something.
Acoustic consultants are extremely expensive, may require many hours if the sound is only apparent during random hours, and even then may come up with nothing.
An app that would at least be able to give a good estimate of the direction from where a sound is coming would be extremely helpful.
Bluetooth/wifi is good for at least a few meters, and should have latency of around a ms. Should be pretty easy to synchronize via that.
Amusingly, data collection would be easier with analog technology. Get some VHS walkie-talkies, and, at the base station, feed all the channels into a multitrack tape recorder like musicians use. No sync problems.
Given that it was intentional, what makes you think it'll be "fixed"?
I remember years ago I had the idea that if you could design construction equipment to rotate/oscillate/whatever at frequencies that were harmonic with each other, construction noise would become musical, almost like a very loud set of wind chimes.
[1] Normally one every 5-10 minutes from 0500 to 23000 since we're on Heathrow approach and not far off City's path.
i found a couple more video examples of accidental acoustic wind effects in architecture -- but it looks like these aren't as ever-present and loud as the Golden Gate Bridge is right now.
Beetham Tower - Manchester, UK: https://www.youtube.com/watch?v=Y8-MrU6lpwg
Freedom Tower - NYC, USA: https://www.youtube.com/watch?time_continue=25&v=nkjA3BvvOuw
in the Beetham Tower case, apparently the architect lives in the tower's penthouse. i bet they're frustrated that none of the fixes have completely remedied the problem.
links from: https://gizmodo.com/when-buildings-howl-a-primer-on-architec...
People who live nearby don't notice it (strange looks if you point it out) but I think it's sad that it's impossible to escape the constant noise in certain places.
My prediction is this will be added to the long history of engineering disasters. It's OK, this is how we learn.
Here's another video I found:
https://en.m.wikipedia.org/wiki/Tacoma_Narrows_Bridge_(1940)
Pretty sure every bridge engineer knows that one. Amusing that the lesson didn't generalize.
My two favorite examples were:
The Therac-25 — it’s just frontend GUI code. Why test it? What could go wrong?
The Siberian gas pipeline explosion of ‘82 — not technically an accident, but it shows the problem with testing untrustworthy code to correctness. It was also the biggest non-nuclear man-made explosion, at least at the time.
The Russians had stolen some pipeline schematics from US companies. The theft was discovered before they stole the control software. Instead of stopping the software from being stolen, US intelligence modified it so an integer would overflow after a year (or two) of operation. The Russian economy would be ruined if the pipeline wasn’t operational in less time than it would take the bug to trigger, so it wouldn’t show up in testing.
When it triggered, it slammed a bunch of valves shut, causing multiple parts of the network to explode at the same time.
The US military’s seismologists detected it, and thought the Russians had detonated a new type of nuclear weapon. The military was going to escalate until the intelligence service told them they were responsible for the blast.
Here’s a decent list of other incidents:
https://royal.pingdom.com/10-historical-software-bugs-with-e...
I highlighted an example of a more catastrophic mistake, familiar to engineers, which was apparently forgotten in this case. Bridges are resonant structures; this is 100% predictable through modeling but that was not done.
Sibling comments point out the Hyatt walkway (news to me, I only took first year mech eng but learned about "galloping Gertie" in elementary school because it was a local and recent catastrophe). Other comments note that the construction crew must have noticed. That this was not escalated points to a communication breakdown similar to the root cause of the Hyatt walkway.
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| | |Running a brace might not be a bad idea, but i could imagine that it might just double the octave, and make it a bit quieter
Be sure to review the first one on yelp after the second confirms.
https://www.theguardian.com/us-news/2020/jun/06/golden-gate-...
From your article: "The wind retrofit project is designed to make the Bridge more aerodynamic under high wind conditions and is necessary to ensure the safety and structural integrity of the Bridge for generations to come,” Cosulich-Schwartz said."
This statement doesn't agree with the video's rationale for updating the railings. I'm guessing the new suicide net increased the wind loading, so the handrail had to be modified to reduce its wind loading. Without the suicide net project, I doubt the handrails would be changed. But the suicide net project is contentious politically, so they cannot admit this.
The new handrail uses long, unsupported plates. The old handrail was far more rigid:
https://www.bontena.com/contents/2018/12/Interview-with-Rick...
So then someone would need to custom manufacturer all of those pieces of rubber and then they would all need to be jammed in there. But then the weather would probably degrade then over time.
I just wonder how many millions are going to be spent on mitigating this.
Makes me almost happy for my hearing loss from attending a Jack White concert in a tiny bar where he maxed out the sound system. Although that’s probably worse off.
I wonder if you can hear it from top of Mount Tamalpais?
Bridge engineer cares to enlighten me/us?
I once ripped this mix from, I think it was di.fm or soma.fm, called 'Quiet ambient preceding magnetic storm', but the only hdd it was on broke.
Should be glorious
https://www.exploratorium.edu/visit/wave-organ/