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Ask Slashdot: Hacking Urban Noise?
b1tbkt writes "I live at the corner of one of the busiest intersections in my city (pop. 350k). Although I've replaced all windows, insulated, and caulked every square inch of the place, the fire trucks and cars with obnoxious stereos still regularly intrude on my home office. Most of the noise comes in through the windows. I'm considering mounting an oblong parabolic reflector in the ceiling above the windows with a steady feed of white or brownian noise directed into it (e.g., via a small speaker placed within the reflector) to create a 'wall' of sound that would act as a buffer to the outside world. Active noise cancellation would be nice, too, but that's probably more than I want to take on. I don't see any products on the market for this sort of thing. Does anyone have any experiences to share with similar homebrew noise remediation efforts?"
What you need, if you have the technical know-how (if you are up to the challenge - or maybe the tech' already exists), is 1) a microphone that will detect the noise coming in on a particular vector, 2) a uni-directional speaker (parabolic - they are never 100% uni-directional though) 3) software that will receive the sound, process it, and retransmit the 'inverted' sound-wave back at the source - at the same amplitude. you need to also take into account the distance from the microphone, the speed of sound, and the precise nano-second in which to transmit the inverted sound. It's easy in theory but in practice.... This is essentially how noise cancellation technologies work. It's complicated and don't under-estimate the vectors involved - refraction, caused by an improper calculation of 'direction', will cause leakage and may induce sound-waves that are more irritating to handle than 'normal' sound.
What you need are multiple layers of different acoustical impedance; that is, hard and soft materials layered. Whenever there's an impedance mismatch, radiation gets reflected. An optical analog is a dielectric mirror. However, the really low frequencies are always a problem, and that's where more mass will help.
"Cheap and works every time. After a few minutes, you'll forget you have them in."
I'd suggest the same. I work shifts and needed them to be able to sleep during the day. Now I can't live without them.
Not only sleeping, but programming, reading and other stuff is great with plugs.
But you can't forget them after a few minutes in the beginning.
I tested 2 dozen of them and still I needed 3 weeks until they didn't hurt anymore. If you wear them 8-10 hours, your ears need to adapt.
It _will_ hurt for some time, but then it's heaven.
You don't get $$$ by being lucky unless you inherit it or you hit the lottery.
People are free to move and live where they want. I suppose you want them to stay and suffer the festering blight of poverty and crime? As far as "solving the problems", name one city that has ever solved the problem. You can't solve stupid and the people causing these problems are Stupid incarnate.
I live outside a city and pay no city taxes. I pay county taxes for fire and police (County Sheriff), and a Hospital District and we have our own water district. I take no resources from the cities nearby, but I do spend my money there. When we pay off the bonds on our district, the city plans on annexing my neighborhood. So then I'll get to pay city taxes and get bum fucking nothing in return except a library card. That's when I move further away.
You people who want everyone to live crammed together in some kind of supposed utopia of harmony and efficiency are nuts. City living has it's advantages and its drawbacks and people are free to choose city, suburban or county lifestyles. Who the hell are you to say anything about their choice?
When Fascism comes to America, it will call itself Anti-Fascism, and tell you to give up your guns.
Back OT, however, the answer is triple glazing and lining the outside wall with Noisekiller - which is a polymer foam/lead/foam composite which can silence the sound of a marine Diesel engine in a steel enclosure.
From scarped cliff or quarried stone she cries "A thousand types are gone, I care for nothing, no not one."
Headphones don't block noise and turning them up to block noise will damage your hearing.
Amazon.com has ear protectors and they will help.
Actually some headphones do block noise, by having a mic and playing the reverse sound (180 degrees out of phase).
But in any event, living with headphones on is not an answer.
The sound is coming thru the windows. Even dual pane windows won't help, they simply act as a drum.
Three pane windows help some.
What is needed is a dual pane window where the panes are not parallel. Tipping the top of the outer
pane outward de-tunes the drum, and reduces sound transmission by quite a bit. The further you can tip it
the better is works.
It has the additional effect of cutting insolation, while actually increasing insulation.
Any good galzier could do this for you and there are starting to be some commercial models available,
but custom built is the best way to achieve this.
Sig Battery depleted. Reverting to safe mode.
I lived in slums for the first twenty five years of my life and as a very quiet person (apparently the only one) in uptown Chicago, I had many altercations with assholes who thought that I wanted to listen to their bullshit music at top volume at one AM and later!
I tried working two jobs to keep me away from it and finally moved into what should have been a quiet bldg, it wasn't down the hall was a drunk named Julio who owned a stereo with an automatic changer, and one 45 RPM record that he looped all night with his door open!
The landlord, yelling, nothing helped! One night when Julio was passed out (with his door open) I walked in, oped his window and threw his stereo down six stories to the ally below!
The best part was nobody saw me, and the little shit accused me and made the mistake of attacking me in front of witnesses! Oh joy! He had to move out after he was released from the hospital!
I HATE noise makers!
I killed da wabbit -Elmer Fudd