Vowel change in Australian English.

The dynamic nature of vowel systems has recently been investigated in several English dialects confirming that phonetic disruptions often have systemic consequences and suggesting that change follows predictable patterns of movement. The present paper examines the nature of vowel change in Australian English by comparing two sets of data from different subjects at each end of a 25-year interval. A series of multivariate analyses of variance reveals significant acoustic differences between the two sets of data providing strong evidence for systemic effects. The analysis also indicates the presence of chain and parallel shifts within vowel classes as well as a close correspondence between monophthong and diphthong movement in phonetic space. The observed monophthong/diphthong relationships suggests that change in one class of vowels impacts on the other in a parallel fashion in this dialect of English.