Reduction of flaps: Speech style, phonological environment, and variability

Abstract

Normal connected speech contains a tremendous amount of variability in how a given sound is realized. The current work examines American English /t/ and /d/ in flapping environments. Flaps can be reduced to an approximant or even deleted in connected speech, and this study compares reduction of flaps to reduction of other stops (/p, b, k, g/) in the same environments. The effects of segmental environment (target followed by /l/, syllabic /r/, /∂/, word boundary, etc.), stress (target following stressed syllable versus between two unstressed syllables), and speech style (casual conversation, reading connected text, and word list reading) are analyzed. Target segments are analyzed for presence/absence of a burst and of formants during closure, for duration of the segment and of closure voicing, and for amplitude during the closure or constriction. This project documents the degree of variability in reduction both within and across speakers. Preliminary results show that flaps are reduced to approximants surprisingly often, even in the most careful speech style. The results also suggest that flaps are far more likely to reduce than /p/ or /k/, suggesting that there is a categorical, phonological process at work as well as gradient variability.