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Author Topic: Why can I hear the bass from my neighbour's stereo, but not the tune?  (Read 10730 times)

Offline jeg29

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Why is it that when the neighbors play their music I can't hear the tune but can hear the bass tones so well I literally feel it in my bones? Sometimes I feel like it's giving me heart arrhythmia. Someone told me that they must be using a "sub-woofer". I don't really know what that is but it is strong enough to pass through several layers of wood and concrete in both homes travel through the earth and shake my cabinets yet I can't hear any of the higher notes or melody of the music. Whats going on with that and is there anyway to block that intrusive sound?
« Last Edit: 22/12/2006 23:50:50 by chris »


 

Offline Gaia

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The lower tones have longer wavelengths and travel further. This is why foghorns have a deep sound.
 

Offline daveshorts

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The way that sound waves lose energy is essentially by bits of air next to each other rubbing on one another causing frictional losses.

If you consider how fast two neighbouring parts of a wave are moving in a wave (I have drawn a wave on a string because it is easier to think about, and draw, but the same holds for sound waves). You can have a:
Long wavelength with a low frequency and pitch

the red arrows indicate the velocity of the particles

Shorter wavelength with a higher frequency and therefore pitch


for the same size/amplitude/volume the difference in speed between two neighbouring particles will be much for for the short wavelength so it will have more frictional losses and therefore be absorbed quicker by walls etc.

There is a second effect called diffraction. A long wavelength will tend to bleed round the edge of shadows better than a short wavelength:


The diffraction is in green
vs


So if the sound is going round several corners the long wavelengths will travel further.

Incidently these two reasons are why you can pick up long wave radio 4 in France, but local radio transmitted on Very High Frequency (VHF)  and therefore shorter wavelength runs out after 20-30 miles from a transmitter. The VHF radio is absorbed more quickly, and can't bend round the curvature of the earth.
« Last Edit: 23/07/2007 21:10:58 by chris »
 

Offline neilep

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 A Sub woofer is a supplementary speaker to aid in music and audio visual as well car audio systems.

It produces a very low frequency that is omni directional !..in other words...you can place a sub (almost) anywhere and it will be difficult to hear where the ' boom ' is coming from.

Chances are very good that your neighbors are enjoying ' sub woofer love ' and so perhaps a polite knock on the door  (if they are approachable) to let them know may help you....else a letter might help !!..do you get on with them ? .. It might be wise to check with other people too to see of they are also suffering this noise pollution.

Some subs can go so low that they do indeed make you feel sick !!...I have seen people throwing up after a few minutes !!
 

Offline jeg29

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Thanks so much for the answers to my questions. I see now why I hear it and they don't seem to. I've gone over to the offending car and also to the families door to see what it must sound like to play music with bass that LOUD, But found myself feeling a fool because when I'm right next to it the deep bass isn't that noticeable. The only thing I can think of is to print out this discussion and put it in their mail box. Beyond that I'd have to invite them in to see how it sounds here in our house. I'm afraid I'm not great on conflict especially with neighbors who we otherwise get along with fine. Thanks again
 

another_someone

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The other factor that can sometimes have an influence is whether you are in a space that is just about the right size, and made of the right materials, to cause resonance to occur - this will have the effect of locally amplifying certain frequencies in the sound at the expense of other frequencies.
 

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