How Does Sound Absorption Work?

Sound absorption is the process by which sound waves are converted into heat rather than being reflected back into space. This reduces reverberations and echos which make spaces feel too loud and claustrophobic.

Sound absorbtion works by trapping the airborne noise in porous materials like foam and fabric. This dampens the production of new sounds and makes rooms quieter. It is often used in recording studios and theaters but can be useful in many types of spaces.

There are several different kinds of sound absorbers but they all work the same way. They are generally made from soft materials that can hold the sound energy, acoustic foam, wool or fiberglass insulation, for example. They are designed to have microscopic openings that will trap the sound waves within them and convert some of the kinetic energy of the sound into heat.

The Science of Sound Absorption: Exploring Absorbtion Techniques

The other type of absorber is a diffuser which works by diffusing or scattering the sound waves so they lose some of their energy and decay much faster than a reflected wave. There are also resonant absorbers (sometimes called Helmholtz resonators) which have air cavities that resonate at certain frequencies and convert the sound energy into heat. This is commonly found in cinder blocks that are designed to resonate and absorb crowd noise during a gym game.

Sound blocking is an effective way of reducing the amount of noise that passes through walls, but sound absorption is better for controlling the sound that is inside a room. It is ideal for use in restaurants where customers are talking, clattering plates and so on, and it can create a more comfortable dining experience. Sound absorption products are often rated with their Noise Reduction Coefficient, or NRC, which shows how much noise a product can reduce.