Patent attributes
In a structure of an in-vehicle audio device, the audio system has an audio signal supplying section, an audio signal processing section, a balance adjustment section and an audio signal output section. A right audio signal processing section and a left audio signal processing section in the audio signal processing section perform a process of filtering audio signals supplied from the audio signal supplying section on the basis of a transfer function. The transfer function contains a head related transfer function H(s), a space transmission compensation function G0(s)−1 and a vehicle height compensation function G1(s). The space transmission compensation function G0(s)−1 is an inverse function of a space transfer function G0(s). A filtering process for the audio signal is performed by using the transfer function to guide a driver's visual line to be decreased when a vehicle height is high, and increased when the vehicle height is low.