Absorption (acoustics)

Absorption refers to the absorption of sound waves by a material. The absorption is the "missing piece", when comparing the total reflected and transmitted energy with the incident energy. It is the property of a material that changes acoustic energy into usually heat energy. A material or surface that absorbs sound waves does not reflect them. Absorption of a given material is frequency dependent as well as being affected by the size, shape, location, and mounting method used.A sound absorber is normally a porous material e.g. mineral wool, glass wool or polyurethane foam, but also Micro perforated plates work as sound absorbers.
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