The contribution of dynamic versus static formant information in conversational speech
Keywords:speaker-specificity, formant dynamics, conversational speech, vowel-inherent spectral change
The relative contributions of static and dynamic formant representations to speaker-specificity were investigated in conversational speech and in two vowels varying in inherent spectral change. Using polynomial fits, the contribution of dynamic formant coefficients to speaker-specificity relative to that of the formant intercept was investigated in the diphthongal vowel [ei] taken from English and Dutch conversational speech. The [ei] tokens were sampled from various linguistic contexts and analysed in an LR approach. Results show that formant dynamics contain speaker-specific information in conversational speech even though the high contextual variation seems to reduce its effect relative to that reported by earlier work. Vowels differ in inherent dynamicity and therefore, the added value of dynamic formant information to speaker-specificity was also compared between vowels differing in inherent spectral change. Using Dutch data, the contribution of formant dynamics to speaker-specificity was compared between [ei] and [a?] tokens produced by the same speakers. Formant dynamics in conversational speech only contributed to speaker-specificity in the diphthong [ei], not in the monophthong [a?].
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