How Sound Absorbing Materials Work?

By Author: Kevin Richard
Total Articles: 240
Comment this article

Proper sound absorbing materials is one of the vital qualities that you should have. You may get a clear idea about the principle of absorption by listening to your own voice in a hallway, then going into the living room or the bedroom and collating about these changes.

This difference depends on what happens to the noises when they come in contact with the wall, a floor or any kind of surface.

The best sound absorbing panels and products are the ones that absorb maximum amount of sound. The best absorbents are porous, implying that the material structure basically traps the moving waves of air. Fabrics, for instance, have a tendency to make efficient sound absorbing surfaces as the fibres conveniently trap the waves rather than allowing them to bounce back. The same rule is also applicable for foam, as the structure of this material is extremely good as trapping the waves as they hit it, and this makes it a good option for sound insulation.

You can imagine sound waves as a series of minute balls, which can bounce back on the solid surfaces such as concrete but would get trapped in it. For instance, ...
... a surface or net with a series of gaps in it. As less number of sound balls bounces back, you would hear less sound and therefore have a higher sound absorption level.

This is how noise ordinance works for the sounds in the air, or the sound that travels through the air and hits the surface. However, sound is also transmitted through the surfaces. You are able to hear transmitted sound when someone is walking on the floor above and you hear it through the ceiling. To lessen transmission, it is important to break the route of the sound. Just think about the difference between those balls passing down a slippery slope, and through dense grass. Then again, the energy of the sound should be absorbed.

Once the sound wave is caught within an anechoic chamber, the energy in that sound just turns into heat. The temperature of that heat is not much obviously. Moreover, a substance with good heat absorption qualities will not necessarily provide proper sound absorption. Polystyrene insulation, for instance, will trap effectively but fail to absorb too much sound.

It is also worth mentioning that various frequencies of sound need different types of sound insulation. The main aspect is density, and as a thumb rule the denser the material, the deeper will be the frequency of sound that will be absorbed.

There are some less costly materials also, like sound absorbing panels. Nonetheless, the least expensive but not the best in looks will be empty egg crates. Nonetheless, just a few would seriously consider this last option for their home, unless they have an incredible hiding idea.