A truncation model for the F2 trajectory in syllables with complex vocalic components

Abstract

Phonetic orthodoxy treats the acoustic realization of a CVn, syllable (N.B. V = vowel or glide) as the concatenation of consecutive transitions from one element to the following one in the syllable. This study proposes an alternative view of the acoustic structure of this type of syllable, based on LPC trackings of F2 in sets of selected Chinese and English CVn syllables. The basic hypothesis is that the underlying F2 transitions between any two phonologically adjacent elements in the same syllable (e.g., the C → V1, V1 → V2,…) all originate at the same temporal position—the syllable initiation. Each transition has a specified rate. The acoustic realization will be a programmed “truncation” process; that is, the phonologically preceding transition truncates the phonologically following transition (e.g., the C → V1 transition truncates the V1 → V2 transition; the truncated V1 → V2 in turn truncates the V2 → V3 transition). This model provides elegant accounts and quantitative predictions of the undershooting and overshooting phenomena in acoustic target realization. [Work supported by NSF.]