Dependence of correct pronunciation of Chinese aspirated sounds on power during voice onset time

The length of voice onset time (VOT) in uttering Chinese aspirated sounds, which are difficult for Japanese to pronounce, is an important factor in evaluating the quality of pronunciation. In this paper, both the length of the VOT and the power used during the VOT for 21 single-vowel syllables of six different Chinese aspirates were measured for 40 Japanese students and nine native speakers of Chinese. The quality of the students' pronunciation was evaluated using a hearing test judged by eight native Chinese. The results indicated that the correlation between the quality of the students' pronunciation and the power used in uttering a sound was greater than to the VOT within a certain range of VOT which varied for different syllables. Thus, we conclude that power is also an important factor in evaluating the quality of pronunciation.