Smartphone-Controlled Multi-Channel Surround Sound System

Multi-channel audio systems are widely used in modern sound devices for movie theaters and home theaters. However, most audio files are encoded into stereo tracks. When using a multichannel system to play a stereophonic audio, the system may not produce the best possible listening perception. This study aims to upmix the stereophonic sound to 5.1-channel sound, thereby enhancing surround sound experience. The proposed system extracts the primary sound for the center audio channel and the ambient sound for the side audio channels. The frontal audio channels are reinforced by a special equalization technique. Users can use a smartphone to remotely control the proposed playback. The subjective listening results show that the spatial audio quality outperforms the commercial built-in upmixing especially in spatial hearing. We also hypothesize that there is a trade-off between directional enhancement and spectral balance in the pilot experiment.