To provide a method for localizing sound image of reproducing sound outside right and left speakers, by processing and controlling audio signals which allows sound image localization outside the speakers for reproducing the controlled audio signals by means of a very concise hardware architecture. When the audio signals 1L, 1R of right and left channels recorded on fit media for stereophonic reproduction are reproduced, process to emphasize a factor of a sense of direction that listener's hearing has is applied by delaying phase characteristic of the audio signals 1L, 1R without change of frequency characteristics with increase in frequency to drive the speakers 7L , 7R of right and left channels.