Influences of vehicle exterior design on loudness ratings by German versus Japanese drivers

Quietness is one important aspect of vehicle performance. In recent years, not only the amount of quietness respectively loudness, but also the quality of vehicle sounds have been investigated. Different sound quality indices were developed based on auditory perception characteristics [1, 2]. In most of these studies, auditory evaluation tests were performed by presenting sounds without designated visual stimuli. However, more recent studies revealed that non-acoustical factors can affect loudness evaluations [3, 4]. In actual driving situations, when hearing the interior sound, the drivers are aware of the vehicle design and have an impression of whether they are driving, for example, a sporty or luxury model.