The PC1892 is a specific IC to reproduce surround sound by using phase shifters and a signal matrix. The PC1892 provides wide sound with two speakers, and rich stereophonic sound with three speakers. In case of stereo signal, the PC1892 has the movie mode to reproduce sense of immediacy (for movie) and the music mode to emphasize vocal sound (for music), and it has the simulated mode to make monaural signal into wide deep sound. The modes can be selected freely by using 2-bit parallel control pins. In addition to this function reproducing surround sound, the PC1892 has a general sound processor that has volume, balance, bass and treble control. So it is capable of reducing installation area. All functions for processing signals of base band sound are provided on one chip.