An Experimental Study on Societal Factors Affecting VOT of English Plosives

Abstract

Plosives are integral components of English consonants. In phonetics, English plosives are classified into voiceless plosives /p, t, k/ and /b, d, g/. VOT (voice onset time) was defined as “the time interval between the burst that marks release of the stop closure and the onset of quasi-periodicity that reflects laryngeal vibration”. VOT is a significant acoustic feature and analytic parameter of plosives. Referring to Labov’s experimental model of linguistic variation analysis, this study investigates the influences of societal factors have on the VOT of English plosives.

In this study, 15 English words with word-initial voiceless plosives /p, t, k/ and 15 word-initial voiced plosives /b, d, g/ were selected as reading material; meanwhile, 30 subjects were randomly recruited to read, and audio samples were collected. It is found that the two social factors (gender and regional dialect) selected in this experiment have influences in different degrees on the English plosive VOT of the subjects. The specific results are as follows.

For gender, no significant difference exists between males and females, but the mean VOT of females is longer than that of males, which is basically consistent with previous research results. The underlying reasons of the gender VOT differences inferred by this paper can be physiological and sociophonetical. For regional dialects, the VOT of the subjects were primarily influenced by Southwest Mandarin and Min Dialect, in which the mean value of voiceless plosives was higher and the difference was greater for speakers of Southwest Mandarin, and the mean value of voiced plosives was higher and the difference was greater for speakers of Min Dialect. The results of this empirical study theoretically provide some reference for acoustic researches, and pedagogically, provide some implications for optimizations of English curriculums in university.