facteur de Sabine

CONT: L'absorption à une fréquence déterminée est définie par le facteur ou coefficient d'absorption qui est le rapport de l'énergie sonore absorbée par une surface S du matériau à l'énergie qui vient la frapper. Il ne faut pas confondre ce coefficient d'absorption avec le coefficient de Sabine obtenu par des mesures d'absorption faites en salles réverbérantes.
OBS: Le terme «coefficient de Sabine» est déconseillé.

CONT: The absorption coefficient of a material is ideally the fraction of the randomly incident sound power which is absorbed, or otherwise not reflected. It can be determined in two main ways, and there are often variations in the results depending upon the method of measurement chosen. It is standard practice to measure the coefficient at the preferred octave frequencies over the range of at least 125 Hz - 4 kHz. For the purposes of architectural design, the Sabine coefficient (calculated from reverberation chamber measurement) is preferred. Interestingly, some absorbent materials are found to have a Sabine coefficient in excess of unity at higher frequencies. This is due to edge effects and, when this occurs, the value can be taken as 1.0.
OBS: Reverberation Time. This formula was developed by W.C. Sabin in the late 19th century. The Sabin unit is a measurement of absorption in the range 0 to 1, an absorption coefficient of 0 indicates a material that reflects sound totally, and a coefficient of 1, a material that adsorbs sound totally.
OBS: The name ""Sabin"" (written without an ""e"") is probably misspelled.