Research On Classroom Chinese Language Intelligibility Based On Impulse Response

In our country,there are some problems in Chinese speech intelligibility in ordinary small classrooms and stairs classrooms in universities or technical colleges,and the importance of hearing environment to architecture is often neglected in the early planning period.A high-definition listening environment ensures that students receive more useful information from the teacher's lectures and ensures good communication between teachers and students.In this paper,5 ordinary classrooms and 3 staircase classrooms are selected in DGTC,all of which are not acoustically treated.Subjective evaluation,objective measurement,fitting analysis and other research methods to analyze the Chinese speech intelligibility in classroom.According to the national standard<GB15508-1995>,the subjective speech intelligibility test is carried out in the selected ordinary classroom and step classroom under two conditions of opening and closing windows,respectively.The corresponding subjective speech intelligibility score was obtained.With software Dirac and related equipment,the impulse response of the corresponding measuring points in each classroom was measured under the condition of opening and closing windows.The objective acoustic parameters such as reverberation time RT,SNR Definition C₅₀0 Clarity C₈₀0 and so on are obtained by processing the impulse response by computer.By comparing subjective speech intelligibility with SNR,Definition C50,Clarity C₈₀,Acoustics ratio Ks and Reverberation time.It was found that the higher the proportion of early reflected sound energy,the higher the subjective speech intelligibility score.The higher the proportion of direct sound energy,the higher the score of subjective speech intelligibility.The higher the signal-to-noise ratio?snr?is,the higher the subjective speech intelligibility score is.Classroom reverberation time and subjective speech intelligibility score decrease.If the classroom reverberation time is in the range of 0.5 seconds and 0.7 seconds,a higher subjective language articulation score can be obtained.To explore the relationship between subjectiveChinesespeech intelligibility score and reverberation radius.It is found that if the measuring point is outside the reverberation radius of 2 times,the subjective speech intelligibility will decrease rapidly with the increase of distance.In addition,when comparing reverberation radius,it is necessary to consider whether the measuring point is in the coverage angle of sound source.If the measuring point is beyond the coverage angle,it can not meet the demand of SNR,and the subjective language articulation score will also be low.Finally,by using the statistical software SPSS,the objective acoustic parameters which affect the definition of subjective speech intelligibility score are analyzed by multiple regression analysis,and the objective parameters which affect the degree of subjective speech intelligibility score are obtained.So that the classroom can be targeted to improve the listening environment.