Chinese speech intelligibility and its relationship with the speech transmission index for children in elementary school classrooms.

Abstract

The present study investigated Chinese speech intelligibility in 28 classrooms from nine different elementary schools in Guangzhou, China. The subjective Chinese speech intelligibility in the classrooms was evaluated with children in grades 2, 4, and 6 (7 to 12 years old). Acoustical measurements were also performed in these classrooms. Subjective Chinese speech intelligibility scores and objective speech intelligibility parameters, such as speech transmission index (STI), were obtained at each listening position for all tests. The relationship between subjective Chinese speech intelligibility scores and STI was revealed and analyzed. The effects of age on Chinese speech intelligibility scores were compared. Results indicate high correlations between subjective Chinese speech intelligibility scores and STI for grades 2, 4, and 6 children. Chinese speech intelligibility scores increase with increase of age under the same STI condition. The differences in scores among different age groups decrease as STI increases. To achieve 95% Chinese speech intelligibility scores, the STIs required for grades 2, 4, and 6 children are 0.75, 0.69, and 0.63, respectively.