Low frequency design of car interior sound using distortion products

When considering the acoustic design of automobiles, low-frequency sounds can increase the excitement levels of users. However, there are several problems involved when increasing the low-frequency levels of engine components. For example, it is difficult to balance silence and excitement if the different order component levels are increased. It is also difficult to generate heavy bass engine sounds in the cabin in practical sce-narios. Thus, we consider an application of distortion products in the auditory system of the cochlea. Distortion products are perceived when two or more sounds with slightly different frequencies are played simultaneously. This study was conducted to examine the possibility of realizing powerful engine sounds using distortion products. As the first step for sound design, we investigated the relationship between combinations of complex sounds and pitch perception of distortion products. The results suggested the possibility of synthesizing a low-frequency component using distortion products inside a cochlea.