Context and identification of vowels in speech variation

Abstract

Interpretation of a particular vowel pattern may vary according to the perceived speech patterns of the speaker [P. Ladefoged and D. E. Broadbent, J. Acoust. Soc. Am. 29, 98–104 (1957)]. Formants from a given speaker, using a specific speech style, reflect both anatomical dimensions of the speakers vocal tract and the speakers preferred vocal settings for the context of the utterance. Speech samples of a set of nine vowels in a standard CVC frame [G. E. Peterson and H. L. Barney, J. Acoust. Soc. Am. 24, 175–184 (1952)], recorded from local speakers, were analyzed and resynthesized, manipulating formant values to derive similar formant frequency ratios from different vowel bases. Thus if the listener identifies the vowels according to the formant patterns, the perceived vowel will differ from the base vowel from which it was derived, whereas if the overall formant frequency shift is detected, then the vowel should maintain its identity, differences in quality being attributed to a change of speaker or of speech style. Using listeners from the same speech community, monosyllabic word identification is contrasted with identification of excised vowels to ascertain the effect of word context on distinguishing the relatively long-term formant ratios of the speaker. [Work supported by NIDCD.]