ESTIMATION OF VEHICLE INSERTION LOSS VIA AIR-BORNE SOUND AND DRIVER'S HEARING JUDGMENT BY METHOD OF LIMITS

摘要

The driver's subconscious response to his circumstances often issues via auditory sensations before optical perception with a conscious response. However, most cars are installed with tightly closed interiors and airborne noise controls. Drivers are sometimes disturbed by this situation because of the loss of transmitted sound information from outside to inside the vehicle. In this case, an investigation can be done by measuring the acoustical insertion loss. Results of the insertion loss with formality sound spectrums will be indicated in this report as well as a psychological estimation with a useful index for the evaluation of sound attenuation. This report deal with the measurement of acoustical insertion loss of road vehicles, the calculation of the loudness shift level and the experimental investigation of psychological functions with respect to insertion loss.