Patent ID: 7184558

Claim:
A volume controller for controlling volume balance between a front speaker and a rear speaker located within a vehicle, comprising: a fade volume computing unit for computing an amplifying factor k 1 of an input signal for providing an increased volume at the rear or front speaker by the volume at a prescribed position within the vehicle which is equal to a decreased volume at the front or rear speaker when an input signal is attenuated by an attenuating factor K 1 , so that when a balancing point is moved from the prescribed position, a total volume at the prescribed position is unchanged; and a control unit for multiplying the signal supplied to the rear or front speaker by the amplifying factor k 1 when the input signal supplied to the front or rear speaker is attenuated by the attenuating factor K 1 and configured to deal with a next fade input with attenuations changed by the amplifying factor k 1 and the attenuating factor K 1 recorded and newly set upon completion of the fade volume computing, wherein attenuations when acoustic waves from the front speaker and rear speaker are propagated to the prescribed position are previously recorded, and on the basis of the attenuations, the increased and decreased volumes at the front or rear speaker are computed.