Acoustic correlates of rhythm in New Zealand English: A diachronic study

Abstract

AbstractThis paper reports on a large-scale diachronic investigation into the timing of New Zealand English (NZE), which points to changes in its rhythmic structure. The Pairwise Variability Index (PVI) was used to measure the mean variation in duration, intensity, and pitch of successive vowels in the speech of over 500 New Zealanders, born between 1851 and 1988. Normalized vocalic PVIs for duration have reduced over time, after allowing for changes in speech rate, supporting existing findings that stressed and unstressed vowels are less differentiated by duration in modern NZE than in other varieties of English. Rhythmically, syllable duration may be playing a reduced role in signalling prominence in NZE. This is supported by the finding that there have been contemporaneous changes in pitch and intensity variation. We discuss external and internal influences on the timing of NZE, including contact with Māori, the emergence of Māori English, and diachronic vowel shift.