Can Acoustic Vowel Space Predict the Habitual Speech Rate of the Speaker?

This study aims to find whether the acoustic vowel space reflect the habitual speaking rate of the speaker. The vowel space is defined as the area of the quadrilateral formed by the four corner vowels (i.e., /i/, /ae/, /u/, /alpha/) in the F1-F2 plane. The study compares the acoustic vowel space in the speech of habitually slow and fast talkers and further analyzes them by gender. In addition to the measurement of vowel duration and midpoint frequencies of F1 and F2, the F1/F2 vowel space areas were measured and compared across speakers. The results indicate substantial overlap in vowel space area functions between slow and fast talkers, though the slow speakers were found to have larger vowel spaces. Furthermore, large variability in vowel space area functions was noted among interspeakers in each group. Both F1 and F2 formant frequencies were found to be gender sensitive in consistence with the existing data. No predictive relation between vowel duration and formant frequencies was observed among speakers