20 ms·
Scientists say you can cancel the noise but keep your window open
- jrussino 6y agoI’ve lived in a few apartments that were situated along busy roads. Something like this would be nice, but I’m hopeful that we’ll someday get to a point where (almost) all of the vehicles on our roads will be electric. Has anybody worked out how much of a noise reduction we can expect from that?
- lisper 6y agoDepends on the street. Once you get above a certain speed most of the noise is tire noise, not engine noise. https://en.wikipedia.org/wiki/Roadway_noise https://en.wikipedia.org/wiki/Roadway_noise
- johndough 6y agoIn my experience (living a mile away from a motorway), most of the noise is caused by the wheel bearings of badly maintained lorries instead of tires. One can usually tell by the high pitched noise.
- catalogia 6y agoI'm surprised that noise propagates far enough for you to hear. In my experience, the noise that propagates furthest from roads is the low frequency tire rumble.
- groby_b 6y agoUnless you live in a city, in which case most of the noise is emergency vehicles ;) I'm extremely skeptical this is something that can be addressed by noise cancellation, either.
- bobthepanda 6y agoThere have been discussions about adding back artificial noise, since a noiseless car would be extremely difficult to detect for people who don't have sight. Also a fair amount of noise generated by cars is not the engine; for example, you have the sound of the tires rolling on the pavement.
- asutekku 6y agoMost of the time on certain environments you don’t hear the cars motors at all, all you hear are the tires having a contact with the ground.
- crazygringo 6y agoEdit: removing my comment because I was wrong. Turns out tire noise can be louder. Thanks to commenters below for correction!
- wffurr 6y agoCombustion engine is only louder below about 35 mph. https://en.wikipedia.org/wiki/Roadway_noise https://en.wikipedia.org/wiki/Roadway_noise "...rolling tires driving on pavement is found to be the biggest contributor of highway noise which increases with higher vehicle speeds."
- dashundchen 6y agoIn the US there are plenty of poorly maintained vehicles on the road emitting a lot of other nosies - squeaky belts, damaged or missing mufflers, rattling panels, worn brake rotors or pads. Most states have very lax inspection requirements. Even in my state, which supposedly is one of the strictest on inspections, it's surprisingly easy to have a dangerous failing car pass. Living near a busy intersection you hear all sorts of weird mechanical failures as cars brake and accelerate from the stoplight.
- wffurr 6y ago
- zbrozek 6y agoNoise is a complicated thing. If you're in a neighborhood that's got low-speed traffic and the occasional car engine is what's disrupting your peace, more penetration of EVs will be great. But EVs are also heavy, and cars are getting heavier in general. That isn't going to do you any favors on tire noise. I wouldn't expect the noise coming off of a freeway to change much.
- heipei 6y agoHere in Germany they have deployed so-called "whisper/porous asphalt" on the highways leading into some major city centres. Since it's more porous than regular asphalt it absorbs noise (and rain) much better, but the drawback is that it's more expensive to manufacture and is less durable. Just saying that there are probably lots of different noise reduction techniques that all add up their percentages, but these will only be put in place if noise pollution is taken as serious as it needs to be.
- coredog64 6y agoMy (US) state DOT paved over the concrete highways with rubberized asphalt for similar reasons. The asphalt doesn’t last as long, but it’s quieter and cheaper than concrete repairs. It’s also something that uses up old tires.
- catalogia 6y agoI live next to a busy street with electric trolleybuses (essentially rubber wheeled city buses that use electrical power from overhead lines.) They're very quiet compared to the odd diesel-powered truck, but the tires on pavement still produce a noticeable amount of noise.
- controversy 6y agoEVs will require a mind change. I have a hybrid. I drive it in St Augustine FL, America’s oldest city. As such the roads in the historic district are narrow. When I come to an intersection I have to be especially conscientious because pedestrians are use to engine noise bouncing down the road ahead of the car. People have walked out in front of me unaware of my existence. I normally mouth, “Surprise, motha fucka” or “I’m Batman” when that happens.
- cerberusss 6y agoYeah people will need to get aware of that. I'm European and drive a Renault Zoe. It plays some sort of "whoooooo" noise from under the bonnet/hood when you drive slower than 30 km (19 mi). On one hand, I think it's dumb because why am I explicitly making noise? So I turned it off. But then I scared the living hell out of two shopping ladies when I unintentionally crept up behind them, and now I always leave it on.
- imhoguy 6y agoNot much benefit from any kind of engine and noise when people walk or cycle with earphones. That is very usual view for me nowadays. Worse if they also stare at they phones too - blind and deaf at will.
- ghaff 6y agoI've said this before in comments but I just really have trouble understanding people who can walk--especially in cities--with earphones. I know some are less isolating than others--some like the pass through mode on the Airpod Pros. But I don't even really like earphones on a forest path much less a city street. I guess it's somewhat a matter of what you're used to. I grew up pre-Walkman and have just never gotten into the habit of wearing earphones like that.
- johnny_reilly 6y agoAre you Batman?
- DenisM 6y agoUp from certain speed more noise is coming from wheels, not engine. Especially if there are defects in the pavement.
- closeparen 6y agoReducing the noise floor is likely to make it more disruptive to have the window open, because the intermittent outliers (trains, buses, motorcycles, trucks) will be even more prominent.
- staticassertion 6y agoI live outside Muni/Caltrain. They're not great, noise-wise, but the motorcycles are 10000x worse. I get a number going by a day, and I just can't understand why they're allowed to be so absurdly loud. Buses/trains are relatively quiet, outside of a few edge cases like tracks scraping or honking when someone's in their way - rare occurrences.
- aspenmayer 6y agoMy intuition about this is that the deflection, intensity, and directionality of the noise from motorcycles impacts street level noise more than trains in a rail corridor. I believe that is why good street planning incorporates natural features that absorb and deflect noise, like greenery on street corners, for example.
- yibg 6y agoThe Caltrain (and other trains but Caltrain is more frequent) going by San Mateo is brutal. Their horn is almost constantly on due to the many ground level intersections and they are ear drum busting loud (by regulation no less).
- staticassertion 6y agoYeah, I do imagine it depends a lot on where you are. Even a few blocks from here the Caltrain can get much louder.
- Symbiote 6y agoThat seems excessive (from a YouTube video). In Britain, within towns there's usually gates on either side of the road, so it's not necessary for the train to use its horn. https://youtu.be/uaWG04vKYLg https://youtu.be/uaWG04vKYLg
- stared 6y agoPersonally, I would favor "noise tax" for any noise generated, regardless of the reason. (I may be biased, I am noise-sensitive.) In this case, it will put pressure to avoid, or reduce, noise when possible (as it directly lowers costs). It's not only cars - all neighbors with a passion for loud music (or quarrels), repair works taking longer and louder than necessary.
- alextheparrot 6y agoIf someone had to pay $1 to use their car horn I think we’d have much better drivers as well
- jacquesm 6y agoMost Romanian drivers would be bankrupt within a day or so.
- etrautmann 6y agoI absolutely detest Harley's and other loud motorcycles and don't understand why there are no restrictions on vehicular noise. Why do certain individuals get to impose their absurdly loud vrooms on everyone else just because they want to? It's such a trivially stupid negative externality that has no reason to exist.
- alonmower 6y agoThere are. They can and should be ticketed if they remove their mufflers or put in exhausts above the legal limit but lots of them DGAF
- angry_octet 6y agoThis is the whole point of riding around on a vibrating sex toy -- to be obnoxious to everyone else, to shout 'look at me'.
- sp332 6y agoHarley Davidson was held sued by the EPA for selling aftermarket "offroad-only" parts for customers' daily drivers. https://article.images.consumerreports.org/prod/content/dam/consumerist/2016/08/env_enforcement-2608482-v1-harley_davidson_complaint.pdf https://article.images.consumerreports.org/prod/content/dam/...
- kortilla 6y agoI used to live along Lawrence expressway in the Bay Area. At 45-50 mph, the noise that drown everything out was the tire noise. The Teslas were just as bad as any other modern ICE car. Where the engine noise was noticeable was low speed intersections when cars would accelerate and the tire noise would be negligible.
- ericmcer 6y agoIt would actually be fine with current gasoline cars minus motorcycles and small handful of people who purposefully make their vehicles loud for... who knows what purpose.
- noir_lord 6y agoMotorcycles as stock under EURO5 typically aren't that loud, it's the obnoxious after-market exhausts that make them so loud particularly with the baffles removed. I find it obnoxious and I am a motorcyclist.
- flanbiscuit 6y ago> but I’m hopeful that we’ll someday get to a point where (almost) all of the vehicles on our roads will be electric. While we wait for that why can't architects/planners take soundproofing more seriously (if they've considered it at all) and actually make the walls and windows inside a building soundproof. It's not even outside noise, I lived in apartments where I could hear my adjacent neighbors.
- sjg007 6y agoThe EPA has noise abatement regulations. Your city and state may also be involved. A lot of things are exempted usually though, such as trains, planes and automobiles.
- mikestew 6y agoAfter about 20mph, tire noise will overwhelm the noise made by even a (modern) ICE. Don’t get your hopes up. Granted, electric takes away the thing you attach a jackassly loud exhaust to, but tires are noisy.
- cadence- 6y agoWhen it comes to passenger cars, most noise is generated by tires hitting the road. Especially at higher speeds the engine noise doesn’t really contribute anything meaningful to the noise you hear. So electric cars won’t solve this problem.
- fxtentacle 6y agoWhen I was living in Singapore, all the rich people were on the higher floors where you don't hear the road anyway. Or they had their own villa with garden. Back then, noise pollution was considered mostly a poor people issue. Glad to see that they are now finally getting an upgrade, too :)
- oh_sigh 6y agono paywall: http://archive.is/zo83N http://archive.is/zo83N
- enitihas 6y agoThis will be revolutionary if it is deployable at scale. One thing I have learnt over the years is to avoid apartments which have any windows towards the road.
- deleted 6y ago[deleted]
- hwillis 6y agoWith certain windows, for certain sounds, you can put actuators on the window itself. They vibrate the glass as a speaker. Unfortunately it is very tricky- the resonant frequency of glass panes is far lower than sound, so its very hard to make the glass all move together. Instead it prefers to take on wavy bends, which can even create their own noise. One neat idea is electrostatic speakers! They're one of the more exotic speaker types, but have unparalleled quality at low volumes. However they are prone to distortion as volume increases and require high (100+) voltage supplies. They can be dangerous and fragile. The idea is you stretch a mylar film very tightly into a rectangle, and then sandwich it between two metal meshes, with an air gap. By putting voltage on the meshes, static electricity pulls the mylar forward and back while keeping it almost perfectly flat. You can put meshes (or ITO films) inside a double pane window to create a very even force over the whole window, making it an excellent transducer. It requires far higher voltages to move glass, though. Putting mylar in between the panes doesnt work (you need some free space to create proper cancellation- oversimplifying) and putting mylar on the outside is dangerous. Tricky problem.
- eternalban 6y agoYou mentioned danger twice. Can expand on this aspect of the tech?
- hwillis 6y agoBy the nature of the device the meshes need to be fairly exposed. They can be enameled so as not to shock you, but only barely. Any scratch, rubbing, or other wear can expose bare metal at >1 kV. That is a major fire risk; any spark is presumed deadly in electrical engineering. Dust accumulates everywhere, and you'd be amazed how much people mistreat electronics. Leaves, dirty laundry and dust may as well be tinder. The even bigger concern is mostly that a moderately loud speaker system (>50-150 watts) can electrocute you. I mean that literally, as the portmanteau of electricity and execution. 1 kV is easily enough to put electricity through your heart; 50 milliamps would be lethal. 50 mA at 1 kV is only 50 watts, less than a laptop charger. A big set of electrostatic speakers can just stop your heart if you're very unlucky.
- klyrs 6y agoThis invention seems like something straight out of a Sharper Image catalog. Neat concept, but needs a few generations of miniaturization before I'd remotely consider it.
- djhaskin987 6y agoIf you're going to put up a wall up on your websites, make sure they load right away instead of loading the whole article before the paywall gets loaded. I was able to read this entire article despite its pay wall by screenshotting the article before the pay wall came up. I had to reload the page, screenshot several times, and time it right but I was able to read the whole article.
- hanniabu 6y agoYou can also read it by viewing the source or by deactivating the paywall
- ip_addr 6y agoOn sites like these i've started disabling javascript.
- wizzwizz4 6y agoPrivate window, enable JavaScript, bypass GDPR banner, disable JavaScript. (Though I'm boycotting NYT until the risk to Scott Alexander has passed.)
- ilarum 6y agoJust press Esc to stop loading the webpage before the wall shows up. Needs practice to time it correctly, but it works well. Other option is to just disable JS.
- atum47 6y agoI'm actually, right now, spending about 6k trying to sound proof my work area. If I ware a billionaire, I'd give these people millions of dollars as investment. Or to another team that could figure it out how to turn your hearing on/off on command.
- jacquesm 6y agoBefore you drop all that money try this: run low volume ambient noise such as rain or distant thunder. That serves as a masking sound and will have a strong effect on getting rid of other non-periodical sounds. Your brain just tunes it out after a while and it tunes quite a bit of the background noise out with it.
- atum47 6y agoyes, that's what I've been doing until this week. but since I'm looked inside the house since Feb this year I'm not spending money on anything. so I decided to give myself this cool room. I'll do a 360 picture of it after it's done. like I did with the victorribeiro.com/3Dsphere but with picture instead of a render
- jacquesm 6y agoThat looks gorgeous. What did you use to make the rendering? Please let me know when you have it all built I'm very curious to see what it will look like in real life. And don't forget to take 'before' and 'after' readings with a sound level meter!
- Faaak 6y agoI'm always dumbfounded when I see that noise emissions are still not taken seriously and not enforced. I live near a freeway and the cars don't bother me that much (I'm far away that they sound like white noise). But the motorbikes, however, are the works. Some of them don't make that much noise, but the outliers make you go crazy. It's a shame really
- pbhjpbhj 6y agoI was born in the country (UK) we could hear individual cars coming from a mile away. We live about a mile from a 2-lane motorway: it's been bliss for me in the depth of lockdown that at times it's been silent, and again I've been able to hear (quietly) individual vehicles at night, or none at all. My kids, brought up with it, were surprised to even be told there is motorway noise, they simply don't notice it.
- ghaff 6y agoYeah, you actually need to be pretty far from roads with any traffic not to hear anything at all. I'm maybe 500 feet from a 2-lane road and about a mile from an Interstate in a fairly spread out area. It's not exactly noisy but with windows open and no music or anything playing, you definitely hear the road traffic.
- techsupporter 6y ago> but the outliers make you go crazy Agreed, so very much. I live across the way from an old-age care home and, based on stereotypes, you'd figure that would be quiet living. Not so much. Their landscaping crew gets out with leaf blowers every day, they have a weekly generator run-up test that lasts for half an hour and pulses with a deep bass, and every few hours on every nice day they pump out the best hits from the 1940s and 1950s on their outdoor patio. Almost all of these are louder than the city's rules permit but code enforcement has told me that because both buildings face each other over a privately-owned parcel (one of these "privately owned public spaces"), the noise transmission rules do not apply. I found this out after I called the care home, twice, to ask if they could maybe turn down the music or do the generator test later in the day (when more people are out and it would be drowned out by other ambient noise) only to be told, politely, to bugger off. I like living in a city and am not going to move--it's not that annoying, compared to benefits I get in return--but sometimes I wish the commons weren't so tragedy.
- ed 6y agoA low tech alternative mentioned in the paper is the Plenum Window. Imagine sliding glass shower doors, but with a bigger gap between panes for airflow. It also claims 10dB reduction, and doesn’t need a computer :) Also from the paper: typical noise cancellation systems create local dead zones of radius ~1/10th the wavelength of blocked sound. E.g., you can block a 1KHz wave within 3.4cm of an error correcting microphone. Good enough for noise canceling headphones but not a whole room. This work builds on an earlier finding that you can treat the window itself as a point source. Noise cancellation at its source is much more effective, so this way they’re able to create a dead zone the size of your apartment.
- cheerlessbog 6y agoThat's with one microphone and presumably a single speaker. I wonder how well one could do with several microphones around the room and several speakers, with their relative positions known accurately and some computing power to generate the best possible reverse sound distribution.
- deleted 6y ago[deleted]
- ed 6y agoYou’d need a lot of speakers (one every 6.8cm) to get the same coverage with an array inside the room.
- TheOtherHobbes 6y agoAnd it's a much harder problem, because antiphase sound from multiple sources will interfere with itself and probably also interact with room resonances, potentially making the problem worse in some locations.
- contravariant 6y agoI reckon the attenuation you can get will be something like the cosine of the phase difference between the speakers. Basically you'd need to them to be much closer than a single wavelength, otherwise they'll amplify the sound, rather than attenuating it. I reckon you could probably do some extremely local noise cancelling (which would only work for a few people at most), but then the speakers don't only need to balance out the external noise, but also each other, which could require extreme volumes if the distributions of speakers is a bad fit.
- rdiddly 6y agoCreating a negative copy of the ambient noise - won't that increase the noise for everyone else? Say you live across the street from a neighbor who has this device. Street noise happens. It reaches you, and your neighbor's cancellation device, at roughly the same time. The device creates the cancellation wave, timed perfectly for the neighbor. That wave also propagates back toward you, and you hear it as an echo, with a delay corresponding to the width of the street.
- ed 6y agoSound decays exponentially as a function of distance, so speakers close to you don't need to be loud. Also most speakers are also fairly directional, so i'd expect any extra energy to be absorbed by the room (as heat). Edit: more importantly these are destructive waves, so if anything you’d actually reduce reflections back out into the world.
- Robotbeat 6y agoNot exactly exponentially.
- vages 6y agoYes, it's not exponential. The sound level is inversely proportional to the square of the distance.
- gmantg 6y agoThis is 1/d^2. Exponential would be 1/2^d.
- anticensor 6y agoIt is actually between the two because sound is a material wave and air has friction.
- 6y ago
- calf 6y agoThe reverse, a cancelling field for outgoing noise, would be great for practicing music instruments, or guest parties, times when you don't want to disturb neighbors (or roommates). Do the scientists discuss this?
- jacquesm 6y agoFor many instruments the solution is simple: practice on an electronic version. This obviously does not hold for all instruments and not all kinds of practice but it can have a big impact. It has an additional bonus too, you can put on a headphone and cut the outside world off as well so it works in both directions.
- calf 6y agoI play classical piano, it's really just not the same hehe. At least, the consumer technology is not quite yet there.
- odiroot 6y agoThis is actually very very important in Singapore. There's multiple highways (sic!) going through the middle of the city. Even on higher floors (say 15 - 20) the constant noise is unbearable if you live on top of one. I didn't notice many sound isolating walls there either. Guess people who were born there get used to it.
- travmatt 6y agoThere are costs to being exposed to high levels of ambient noise though: https://www.euro.who.int/__data/assets/pdf_file/0008/136466/e94888.pdf https://www.euro.who.int/__data/assets/pdf_file/0008/136466/...
- lgas 6y agoOut of curiosity, what's the idea behind including a "sic" parenthetical in an original unquoted piece of writing?
- wizzwizz4 6y ago"Sic" means "that's not a mistake". When quoting, it often means "I didn't make the mistake, I faithfully copied somebody else's" but when writing your own stuff, it means "I didn't make a mistake; I meant to write that".
- lgas 6y agoOk, gotcha. I'm familiar with it (in the "sic erat scriptum" sense) for other people's writing but I've never seen it used in an original writing like that. Not sure I get it here either, since most cities I can think of have multiple highways going through them, but thanks for the clarification. Always glad to expand my understanding of language.
- TheOtherHobbes 6y agoIt literally means "thus" which is just another way of saying "Yes, really!"
- sjg007 6y agoThe other solution here is to put the speakers on the window frame, then you can do some projection etc...
- deleted 6y ago[deleted]
- jacquesm 6y agoVery timely. So, after boycotting a certain manufacturer for more than a decade on account of their root kit debacle I finally relented and spent some money on a noise cancelling headphone. It works pretty good, the tech has matured and the difference between NC on and off is remarkable. Even a neighbour mowing their lawn or using a chainsaw disappears to the point that I can focus on playing an instrument or writing a piece of code or text. This was a key element for me in overcoming my insomnia, I used to stay awake at night because it was finally quiet enough that I could concentrate. After identifying that as a key part of the problem noise reduction became a focal point. It has created a new problem: the headphones are so good at this that it is very easy to creep up on me and scare the bejezus out of me when I don't receive any other clue such as a changing shadow or something like that. I'll have to figure out some kind of early warning system for approaching people. Whoever cracks this particular nut without headphones and manages to create a bubble of 2 cubic meters or so that is silent from outside interference will make a lot of money. The article lists one entrant that seems to be a move in the right direction but it does not look like that particular version will be ready for prime time in the near future. My 'ideal' soundsucker (sonic black hole) is a ceiling mounted device that projects a cone of silence. One possible way in which it could work is by using a phased array of speakers to 'fake' a larger one. But that ideal will likely never be reached due to limitations in physics, imagine the problem as applied to a wavy surface of water: create a wave pattern that cancels out the wavy surface in one circular area without touching the water directly. Edit: Another - unexpected - benefit is that all the fan noise and other ambient noise in the room I'm in (which I normally don't even notice) also drops by a very large factor with NC enabled.
- hinkley 6y agoAmongst the stereotypical conference swag, there used to be a tiny fish-eye mirror with a notch out of the back, so that you could affix it over the corner of your monitor. Poking around I couldn't find them, but there are rather a lot of tiny fish-eye mirrors being sold to affix to the top or corner of a car rear view mirror (so-called blindspot mirrors). Those should be in roughly the correct size classification.
- 6y ago
- deleted 6y ago[deleted]
- lostlogin 6y ago> Dr. Lam explained that “in places like Singapore, we want to keep the windows open as much as possible” I haven’t spent a lot of time in Singapore but the time I spent there had visibility of about 50m from the burning of scrub/jungle in Malaysia and the air quality was abysmal.
- rorykoehler 6y agoIt’s unusual for there to be haze. When there odds have it’s awful but it only happened twice, once bad and over mild, in the 4 years I lived there.
- lostlogin 6y agoThanks, things must have improved as its 10+ years since I was there and it didn't seem an unusual event then.
- rorykoehler 6y agoThey started suing the companies responsible after the 2014 (?) Indonesian forest fires. Seems to have been effective.
- davidhyde 6y agoTechnology for noise cancelling headphones is fairly straight forward. You put a mic near the entrance of the ear and then reverse the wave. The ear is basically a one dimensional sensor in that configuration. Now, take the headphones away then think about what you have to do to cancel noise. You have this two dimensional window in your home that lets through three dimensional sound waves. The best that you can manage is a two dimensional speaker array which is what you see there attempting to create some sort of sound hologram. It’s insanely complex and anyone who thinks that a company who makes good noise cancelling earphones would therefore be capable getting technology like this to work is just very naive. It’s another magic leap. A whole bunch of people who think they are not buying into snake oil when they really are.
- jacquesm 6y agoThree dimensional speaker arrays are definitely possible, a simple one would be a cube, a bit harder would be a cylinder. Yes, it is extremely hard. The question is though, can it be done? Phased arrays are insanely hard as well, they do work though. In the 80's there was a free space noise cancelling demonstration on a cross roads in a major city somewhere, I can't seem to dig up any references to it. IIRC that was a completely analog setup, I have no idea how it worked but they had a volume within which background noise was substantially reduced. I can't stand it when I am 100% sure that I read something but I can't find it.
- leeoniya 6y agoLight Field Cameras (with arrays of micro-lenses) also seemed extremely hard (to me), yet Lytro managed to get the tech working at non-laughable resolutions in a small package, so...shrug.
- amelius 6y agoYes, but we're talking about a device here that's not sitting in front of your window, but makes it look black.
- coldtea 6y ago>Now, take the headphones away then think about what you have to do to cancel noise. You have this two dimensional window in your home that lets through three dimensional sound waves. The best that you can manage is a two dimensional speaker array which is what you see there attempting to create some sort of sound hologram. First, what you be the problem of creating a three dimension speaker array? Sounds totally feasible... Second, is that really "the best" that we can do? I've read about a mesh of special design that you can put on your window that still lets you see outside and lets air go through, but cancels certain movement/frequencies, cutting off noise.
- temptemptemp111 6y agoI investigated this exact idea about a decade ago with a bunch of engineers. We all concluded it was too difficult to be worth it. Wise engineers live in the country :)
- blahblahblogger 6y agoCan the outside world hear in though? People may forget themselves and lose sense of perspective. I have a bipolar condition where sometimes I'll pace my apartment and yell about anything and everything, if I lived in one of these places I imagine it'd exacerbate things and bother the neighbors too.
- deleted 6y ago[deleted]
- snarfy 6y agoI tried making something like this for closed windows out of a pair of broken NC headphones and some surface vibration speakers stuck to the window. It didn't work very well. This did get me interested though and am curious of what software libraries and solutions are out there for noise canceling. I would very much like to hook a mic and speakers up to a raspberry pi and get some of the road noise reduced. I'm not sure where to start with software though. I know the basic premise is invert the signal coming from the mic and output that. That's not exactly state-of-the-art though.
- sjg007 6y agoInteresting. I always thought that the window would make a good speaker. So.. what issues did you run into? You say it didn't work very well? Did you account for the delay? It sounds like this should work...
- snarfy 6y agoI took the NC headphones apart. I added wires to the mic used for noise cancelling and hung it out the window, closing the window around the wires. I added wires to the headphone speakers and connected them to a small amplifier that was hooked up to the surface vibration speakers. It took about an hour to do. When it was on and NC was engaged, it was actually louder in the room when a car drove by. The counter noise was adding, not subtracting. It's was a quick and dirty hack. I assumed the physics and algorithm they use requires the mic to be closer to the speakers and gave up. It would have been pointless to try to modify it further. That's why I was hoping there is a software solution that I could actually have a chance of modifying and e.g. fix the delay if that is the problem. Maybe even a ML solution.
- sjg007 6y agoYeah should be possible. I am thinking of working on this. Not sure if an ML solution is necessary but it would be cool and would work.
- Fice 6y agoCould this problem be solved with an adequate ventilation system, so there will be no need to keep windows open?
- gliese1337 6y agoImportant distinction: this is an epistemic "can", not a deontic "can". In other words, they are saying that it is possible to keep your windows open if you want to and still not let noise in--not that you are permitted to cancel the noise, but must keep your windows open anyway. I had initially thought this would be something about indoor CO2 buildup or something, but no.
- anonmidniteshpr 6y agoI don't see how it's possible to win ANC against loud, booming, tiny reproductive bits car stereos driving by wannabe cholos because the speaker size to produce phase-canceling mirror sound would have to be 10-12" / 25-30cm and placed probably on 3 sides minimum... say 12 speakers or 24 for all 6 sides. And the SPL of the ANC would need to be sized proportional to the most powerful car stereo one wished to block.
- rossmohax 6y agoIs it possible to solve it mechanically? Like airtight, soundproof windows for light and S shaped duct padded with acoustic foam for ventilation?
- lambdatronics 6y agoHere's a low-tech approach: fill the window with staggered plastic straws. You don't get much of a view, however, and the airflow would be impeded. https://www.researchgate.net/profile/Martin_Tenpierik/publication/336700023_Drinking_Straws_as_a_Broadband_Sound_Absorber/links/5dadc85ba6fdccc99d92851a/Drinking-Straws-as-a-Broadband-Sound-Absorber.pdf https://www.researchgate.net/profile/Martin_Tenpierik/public...
- eejjjj82 6y agoFor anyone interested in building this DIY on a smaller scale I highly recommend this Tech Ingredients youtube channel's video: https://www.youtube.com/watch?v=--c0tiIZG6o https://www.youtube.com/watch?v=--c0tiIZG6o This is by far the nerdiest channel I subscribe to and I LOVE it.