Abstract:
As vehicle interior noise levels decrease and customer expectations of comfort increase, measures of sound-pressure level are no longer sufficient to characterize the acoustic environment of the vehicle. It therefore becomes important to study other sound attributes that affect customer satisfaction. A procedure has been developed by which customers identify and evaluate the important powertrain attributes, using the semantic differential technique. The attributes fall into two categories, psychoacoustic (loudness, roughness, pitch) and ``halo'' (expensive, reliable, powerful). By correlating the semantic result with preference data, it can be determined which attributes contribute most to customer preferences. Attributes important for one market segment may be unimportant for another segment. The semantic differential results are correlated to objective sound quality metrics. Comparison of the results across compact, midsize, and luxury market segments will be discussed.