PURPOSE: To stabilize the localization of a sound image by turning a switching circuit OFF by a control circuit and driving only two speakers when an identification signal which is not stereo broadcasting is supplied.

CONSTITUTION: A control channel circuit 4 discriminates whether signals received at present is monaural broadcasting, stereo broadcasting or bilingual broadcasting from audio signals 11 and inputs the discrimination signal 13 to the control terminal of a signal switching circuit 5. Then, at the time of receiving the stereo broadcasting, a control, circuit 50 turns the switching circuit 40 ON and drives not only first and second speakers 30 and 31 but also third and forth speakers 32 and 33 and surround reproduction is attained. Also, at the time of receiving the bilingual broadcasting or the monaural broadcasting, the control circuit 50 turns the switching circuit 40 OFF, stops driving the third and forth speakers 32 and 33 and drives only the first and second speakers 30 and 31. Thus, the sound image can be localized at the time of receiving the bilingual broadcasting or the monaural broadcasting.