street traffic sounds reduction

[vbr666]

hi.

 

i've got a very real life question and im wondering if this is the right place to ask it, but here it goes.

 

i've rented an apartment which is next to the main street so i have trouble sleeping after 5-6am due to the traffic noise.

 

since i cant make any serious modifications to the apartment cause i do not own it, i was wondering would it be possible to produce sounds which would help me sleep, which would actually "soften" traffic noises, or create some kind of counter waves which would reduce the street sounds?

 

my idea was to automatize my laptop to turn on in the morning and start playing those sounds and continue doing so till i wake up and turn it off.

 

of course, the trouble is i dont know much about physics or nature of traffic sounds, I mean, i can't experiment with them cause ive got no gear to do so.

 

i dont know which software to use to maybe try playing sounds randomly and creating tolerable environment for sleeping in my bedroom.

 

any kind of help, advice or guidance is much appreciated, so thanks in advance.

Edited November 9, 2010 by vbr666

[zapatos]

I turn on a fan close to my bed, switched to high. Worked wonders for me.

[michel123456]

I know only some basics about sound. The intensity of sound is measured in Decibels, which is a logarithmic scale. Why logarithmic? because sounds don't add. A sound of 10 Db plus a second sound of 10 Db do not produce 20 Db, but slightly more than the originals 10 Db. In your case, if you add some soft music, or a "white noise", like the noise of the sea, or that of a soft breeze through palm trees, you may solve partly your problem.

Another solution is simply earplugs.

 

I am afraid "counter waves" are not feasable.

Edited November 10, 2010 by michel123456

[imatfaal]

I am afraid "counter waves" are not feasable.

 

 

Not feasible - quite agree. But are they possible, (money no object)? They work in headphones - Bose and Sennheiser make a fortune selling noise cancelling headphones because they work. Could not an array of microphones around bed allow a fairly accurate model of the incoming sound waves to be made and feed information to processor to produce signal for speakers to create noise-cancelling out of phase sound.

 

 

[tomgwyther]

Could not an array of microphones around bed allow a fairly accurate model of the incoming sound waves to be made and feed information to processor to produce signal for speakers to create noise-cancelling out of phase sound.

 

This would be pretty much impossible in an acoustic environment, Such as a bedroom.

Unless: If the offending noise was coming through the window, you could place a microphone outside, with an array of speakers covering the window inside. Then use the same phase altering hardware as described in the noise cancelling headphones to cancel the noise coming through the window. Probably be cheaper to buy a new apartment though.

 

you could get a second glaze on the window. i.e. a sheet of perspex which could be attached to the window frame without damaging it. this also keeps the heat in during the winter.

 

You could also try sleeping with earplugs, although this might not be ideal as they can get itchy, plus you can hear your own breathing, heart-beat and other bodily noises, maybe a little too clearly.

 

you could build a sort of 'vocal booth screen'. I use them in the studio to cut out ambient or extraneous noise.

It would basically be a piece of plywood, with one side covered in acoustic tiles. If it were the same size and shape of the window, you could put it in the window frame at night and take it down in the morning.

 

The cheapest option maybe to simply 'get over it'. I mean this in the nicest possible way.

it's likely that after a while, your brain will get used to the traffic noise and not wake you up too early.

When I moved to my house, the church opposite would wake me up early on Sunday by ringing its bells. these days I don't notice it.

[michel123456]

Not feasible - quite agree. But are they possible, (money no object)? They work in headphones - Bose and Sennheiser make a fortune selling noise cancelling headphones because they work. Could not an array of microphones around bed allow a fairly accurate model of the incoming sound waves to be made and feed information to processor to produce signal for speakers to create noise-cancelling out of phase sound.

 

From wiki article "Retail noise-cancelling headphones typically use ANC to cancel the lower-frequency portions of the noise; they depend on more traditional methods such as soundproofing to prevent higher-frequency noise from reaching the ear. This approach is preferred because it reduces the demand for complicated electronic circuitry and at higher frequencies, where active cancellation is less effective. To truly cancel high frequency components (coming at the ear from all directions), the sensor and emitter for the cancelling waveform would have to be adjacent to the user's eardrum, which is not technically feasible."

 

In other words, companies are making money upon people's ignorance or uninterest in physics. (I couldn't fin a sweetest way to write it down without hurting anybody).

 

_If you want to improve soundproofing of your residence, they are several ways, some are expensive, some are not.

. the simplest is to look carefully at your windows and close any small orifice. Sound is a wave, and goes through even the smallest holes, then expand again on the other side of the obstacle (the window). Sush holes exist usually in the corners of the windows, where rubber joins at right angle, and at the window hand. There may be other holes in the wall, like air ducts or kitchen exhausts. By closing these holes you will reduce the amount of noise transmitted directly by air.

. you can improve generally the perimetrical rubber band (I hope there is any) putting a rubber from hard material so that the window closes firmly. The sound coming from the outside makes your window tremble, and this trembling transmits the sound in the air of your room. The meaning of this intervention is to reduce as much as possible the trembling of the window.

.you can put a second glass. Either outside, either inside (much easier).The meaning is to put a new heavy obstacle to the sound. The more heavy (the higher density), the best. You can also put a heavy curtain, that won't make much effect, but it has the same meaning. By the way, this intervention could be paid by your owner because it is a general improvement of the residence. You can also put external shutters.

.you can change completely your windows, find a reliable provider with sound-proofing specifications, under the agreement and at the expense of the owner.

.you can ask the ministry of transport & communication to put sound-proofing walls along the main street. It is the cheapest for you & the most expensive for the community.

.because sound makes everything tremble (not only your window), it is probable that some low sounds (coming from a Harley with a hole in its exhaust) transmit to the whole building and to your bed too. Avoid generally your bed to touch directly to a wall or column. It may be that you are not waken by the sound, but by the feeling of the wave through your body.

 

Physiologically, we are made to be sensible to sounds at any time, even when we sleep. Our auditory system is a kind of alarm system that works 24h/24. We don't have eyelids to our ears.

Edited November 11, 2010 by michel123456

[imatfaal]

Michel - yes, to an extent. But I can guarantee that the electric circuits (whatever they are doing) in the bose headphones they give out on american airlines make a noticeable difference on the roar of the jet. They have a switch to turn on the power so you can flip from on to off (ie from just physical soundproofing to active in addition) - and whilst voices are almost unchanged (which tallies with your quote above) the low drone of the engines is considerable reduced.

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