Sound quality of exterior vehicle noise

Abstract

For several years the acoustical engineers from all car manufacturers have been busy investigating and improving the sound quality of the interior noise of vehicles. For 20 years we have been using specific measurement technologies and analyses to describe sound quality with consideration of the signal processing of human hearing. But with respect to the exterior vehicle noise only standard measurements, e.g., the A-weighted sound pressure level, are still in use. Although the A-weighted sound pressure level has been reduced, the annoying effect of exterior vehicle noise and traffic noise has increased. The negative impact of exterior vehicle noise and traffic noise on man must be reduced. Solutions must therefore be found to the vehicle noise emission problem while allowing sustainable mobility. An important prerequisite for improvement of the well-being of the public and acceptance of future traffic and acoustic environments is the consideration of human sound perception of the exterior vehicle. This paper describes how we can transfer the knowledge of sound quality analysis with respect to interior noise to the evaluation of exterior vehicle noise. This includes not only the methodologies for the measurement and analyses, but also the development of a prediction tool.