Investigation on the effects of source directivity of Chinese speech intelligibility in real and virtual rooms

Subjective Chinese speech intelligibility was evaluated by using three sources with different directional patterns: an omnidirectional source, a source with similar directivity of a human speaker, and a human speaker source in both real and virtual rectangular rooms with different reverberation times. The result shows that subjective Chinese speech intelligibility scores exhibit statistical differences under different source conditions. Speech intelligibility scores obtained by using an omnidirectional source are lower than those obtained by using the other two sources. Therefore, the use of omnidirectional sources will undermine speech intelligibility compared with real human speech in rooms. Subjective Chinese speech intelligibility obtained from virtual rooms using auralization is basically similar to that obtained in real rooms under different source directivity conditions. Using the auralization technique enables the proper evaluation of subjective Chinese speech intelligibility with different directional sources.