Experimental study of the sound field in an underground shopping street

Soundscape and sound preference are important in underground shopping streets. In this study, the basic characteristics of the sound field in underground shopping streets have been examined, through a series of measurements of sound level distribution and reverberation. It has been found that in the underground shopping street the sound level attenuates over 30dBA at about 150 m from the source, and the reverberation time RT30 is mostly around 0.6–1.3 s. Along the length the sound level decreases continuously and the RT30 increases systematically, at all frequencies, which are of the long space characteristics, so that long space theories, rather than classic room acoustic theories, should be applied as design tools for underground shopping streets.