Formant frequency variability in English schwa-initial minimal pairs

Abstract

The label “schwa” has traditionally been used to refer to a mid-central vowel produced with a neutral vocal tract. However, “schwa” has also been used by linguists to represent a wide range of sounds cross-linguistically, which show considerable variation depending on their context. Previous research on schwa quality has focused primarily on consonantal factors that impact the phonetic realization of schwa. One understudied factor is whether or not the schwa is a function word (as in a company) or the initial syllable of a content word (as in accompany). The current production study aims to look at both ambiguous (e.g., accompany and a company) and unambiguous (e.g., accomplish and a comic) schwa-initial pairs in neutral sentences, which, up to a critical point, can be read as having either schwa variant, and biasing sentences, which are contextually biased towards one of the schwa variants. Preliminary analyses reveal that F1 at the midpoint of the schwa is not affected by schwa type, ambiguity, or sentence bias but is determined primarily by schwa duration. This result suggests that variability in schwa quality may be a result of its short duration relative to other vowels, reflecting articulatory undershoot.