Experimental comparison of speech transmission index prediction methods based on statistical
Good speech intelligibility is an important goal of acoustic environment design in lecture rooms and auditoria.The speech transmission index(STI)is an objective evaluation metric for speech intelligibility,accurate prediction of STI during the design stage is very important for the acoustic environment control in lecture rooms and auditoria.The statistical-based STI prediction method is recommended by the IEC 60268-16 standard,there is still a lack of systematic research on the influencing factors and prediction accuracy of these methods.In this paper,the influencing factors and prediction accuracy of these methods were analyzed using STI measured results of 52 listening conditions at 13 receiver positions in 4 rooms.The results revealed the followings:There are systematic biases in both prediction methods with and without consideration of di-rect sound,and the predicted results are generally smaller than the measured results.The errors are larger when the receiver positions closer to the sound source,and relatively smaller when the receiver positions are further away from the sound source.The prediction method based on single exponential decay sound field without consideration of direct sound is simple to operate,but with a larger error;the average STI error for the 52 listening conditions reached-0.032 and the maximum error reached-0.131.The prediction method with consideration of direct sound has relatively small errors;the average STI error for the 52 listening conditions was-0.018 and the maximum error was-0.080.The prediction accuracy is mainly influenced by the signal-to-noise ratio used,the directivity of the loudspeaker,the sound field conditions of the room,and the possible influence of these factors was compared and analyzed.The results provide a reference for the users of STI prediction methods.
万方数据
维普
