Sound Absorption Experiment: Research and Testing

[Hazemm]

hey,
I'm starting this experiment regarding Sound absorption, and I am having a little trouble finding sufficient research to describe the physics behind it. Basically, I have a wooden chamber, which i will be testing inside. I will have a signal generator at one end, and a microphone hooked up to an osilliscope, in order to see differences in amplitudes. What I'm testing is how the density and shape of a material(im testing three types of foam, and the empty chamber) affect the amount of sound absorbed. If anyone can help me tie this in more with actual theory, and/or think of any other possible ways to analyze the resulting sound wave it would be a great help. At the end of the experiment i will be writing a 4000 word essay about what I did for my physics course. Anyways, thanks a lot
peace

 

[pallidin]

The article here might be of some help, specifically Part IV:

http://stason.org/TULARC/physics/acoustics-faq/index.html

Here's another site: http://www.soundprooffoam.com/

And here: http://www.engineeringtoolbox.com/accoustic-sound-absorption-d_68.html


Not sure if the above helps, but worth a look.

 

[pavan0007]

hello sir
i am a designer basically into Diesel generators. we are starting freshely into market and i am struggling to design of sound proof cannopy for desiel generator .so please suggest some sites or formulas and what is the starting point of designing of this cannopy.

 

[Ivek]

If you mean what type of element absorbs most sound it will probably be the thickest foam, and least empty chamber because as a violinist i can say wood is a very good sound conductor. Maybe a bad choice of chamber:/