courbe de pondération A

CONT: Courbes de pondération A, B, C. - [...] La courbe A utilisée très souvent pour caractériser un bruit par un seul chiffre, en dB(A), accuse une très forte atténuation des fréquences basses : 30 dB à 50 Hz, 19 dB à 100 Hz [...]

CONT: Weighting filters try and give readings that roughly correspond to the way humans respond to sound. Sound pressure level measurements use weighting filters based on three curves: A, B and C. ... The B-weighting curve is used for [measuring] intermediate level sounds and has the same upper corner as the C-weighting, but the lower amplitude corner is 120 Hz. The A-weighting curve is used for measuring low level signals such as background noise.