Field Versus Lab: Situational Influences on Vehicle Sound Assessment

Although it is agreed in literature that contextual aspects are effective moderators of sound quality evaluation, it is common practice to use results gained in laboratory studies to draw conclusions about customer experience in the real-life context. However, as the contexts differ considerably, such deductions are of potentially questionable value. For an effective improvement of experienced sound quality, understanding its evaluation process is crucial. For vehicle sound evaluation, a comprehensive model was presented in [1] that was obtained from data of a field study. However, it is unclear whether, and to what extent, the same model also can be transferred to listening experiments performed in a lab. In this work, a comparison between field and lab-test results of vehicle sound evaluation is carried out. Ratings of sound quality, comfort, sportiness, type conformity and make conformity were collected in a listening experiment under controlled conditions. The ratings were fed into the sound quality model of [1]. It was found that the sound quality model can also successfully describe lab-test results. However, an increased impact of comfort on sound quality was found, which is attributed to a greater focus of the participants on the mere acoustical aspects and an increased sensitivity to loudness in the lab. Certain specific driving conditions gain higher importance for comfort, such as standstill conditions or dynamic driving. As this can substantially influence the sound quality, the unreflected transfer of lab-test results to real-life contexts is not advised. Finally, evidence was found that the division of subjects into three driver types, as proposed in [2], makes meaningful distinctions with respect to the evaluation of vehicle sounds.