Sound absorption coefficient – this term refers to the ability of a given object, such as an acoustic system, to absorb sound, or the energy of acoustic fields. The coefficient has no dimension and is commonly denoted by the letter α. The ability of a given object to absorb sound results, among other things, from its construction and the material used. In rooms, the so-called reverberation sound absorption coefficient is used. This allows for the determination of the ability to absorb dispersed acoustic energy, that is, to reduce reverberation in a given room.
The reverberation sound absorption coefficient is provided in octave bands, most often from 125 Hz to 4 kHz.
Acoustic systems designed for sound absorption typically have an assigned sound absorption class from A to E, where A is the highest class. Using them in enclosed spaces is an effective way to ensure good acoustics and sound quality during a concert or lecture.
