An apparatus and a method of reproducing a wide stereo sound by widening a stereo sound output by an audio reproducing apparatus using only two closely disposed channel speakers include a widening filtering operation and a direct filtering operation. In the widening filtering operation, virtual sound sources for arbitrary locations are formed from a stereo-channel audio signal using head related transfer functions measured at predetermined locations, and crosstalk is cancelled from the virtual sound sources using filter coefficients in which the head related transfer functions are reflected. In the direct filtering operation, signal characteristics of the stereo-channel audio signal are adjusted based on the crosstalk-cancelled virtual sound sources.