Keywords
schwa
vowel reduction
acoustic phonetics
unstressed syllables
F1
F2
vowel duration
phonetic context
coarticulation
How to Cite
Abstract
Schwa /ə/ is one of the most frequent vowel sounds in English and is strongly associated with unstressed syllables and processes of vowel reduction. Although schwa is traditionally described as a central and relatively neutral vowel, its actual acoustic realization may vary according to phonetic context, syllable position, speech rate, and neighbouring segments. This study investigates the acoustic realization of schwa in unstressed syllables of British English using speech material from the spoken component of the International Corpus of English-Great Britain (ICE- GB). The analysis focuses on three principal acoustic parameters: first-formant frequency (F1), second-formant frequency (F2), and vowel duration. Candidate schwa tokens were identified from the corpus transcripts and examined acoustically using waveform and spectrographic information. An initial set of 59 acoustic candidate observations was subjected to an acoustic quality-screening procedure, resulting in 39 observations retained for descriptive analysis. The screened observations yielded a mean F1 of 462.32 Hz (SD = 79.93), a mean F2 of 1482.06 Hz (SD = 235.49), and a mean duration of 83.59 ms (SD = 41.66). Exploratory statistical comparisons across lexical target groups did not reveal statistically significant differences in F1, F2, or duration. However, the observed dispersion of the acoustic measurements indicates that schwa is not represented by a single acoustically invariant configuration. The findings are discussed in relation to previous acoustic descriptions of schwa, particularly the work of Kondo and Bates, and support an interpretation of schwa as a phonological category whose phonetic realization is sensitive to its surrounding context.References
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