To accurately cope with both of right and left handle vehicles by providing an audio software prepared so as to listen to reproducing sound in balance on a left or right seat side and a reproducing device for reproducing the audio software and equipping a changeover means for performing changeover so as to make the reproducing sound be in balance in the reproducing device.

In a CD:10a, the audio software prepared so as to listen to the reproducing sound in balance on the side of a driver seat 66 for instance is recorded. In this case, at the time of judging that a changeover switch 17a is set to the side of a passenger seat 67, an inversion means 12 is operated and R/L channels are inverted to L/R channels. The analog audio signals of the R and L channels are made to pass through wires 19b and 18b and amplified in a power amplifier 16 and the sound of the L channel from speakers FR and RR and the sound of the R channel from the speakers FL and RL are respectively reproduced and outputted in a balanced state on the side of the assistant driver seat 67.