The article presents, in a chronological way, the main parameters used for automotive vehicles concerning acoustic qualification/quantification. We start with the loudness concept, pass by the ''A'' weighting philosophy and arrive to the sound level reduction including sound quality. We show a lot of parameters, each trying better to match the correlation between objective results and subjective evaluations. We mention several aspects of the human ear that make it difficult to describe sound sensations through a single parameter. We emphasise also the absence of exposure time in the parameters used to evaluate acoustic comfort. We show the large gap between the parameters used in the laboratory and those applied in legislation through standards. Some conclusions are presented and the future, related to acoustic parameters, discussed. (Author/publisher)
Abstract