Abstract: An improved virtual reproducing system for 5.1 channel surround sound and signal processing algorithm of the system are proposed. Firstly, by analyzing the sound field of virtual reproducing systems for 5.1 ch surround sound, it is proved that there are some defects in current systems, including narrow listening area, sound image direction distortion, timbre change in reproduction etc. Then from theoretical analysis, it is proposed that, by decreasing the separated angle between reproducing loudspeaker pair to ±15° and using signal processing algorithm with timbre equalization, the improved system can get rid of the defects of current systems. Additionally, the signal processing algorithm of improved system is also simple. The results of psychoacoustic experiment verify theoretical analysis, and show that improved system is able to recreate sound image in half of horizontal plane (about ±90° in the front. Finally, the system and its arrangement of loudspeakers are suitable to be used in TV sets or multimedia computers.