A cross-dialectal acoustic study of the monophthongs and diphthongs of Welsh

The Welsh language has a complex vowel inventory with up to thirteen monophthongs and the same number of diphthongs. According to descriptive reports, systematic differences are found between the two main varieties of Welsh, Northern and Southern Welsh (Ball & Williams 2001, Jones 1984). However, few studies have attempted to verify these claims instrumentally, and little is known about the acoustic properties of Welsh vowels. The present study is the first systematic acoustic investigation of the monophthongs and diphthongs of Northern and Southern Welsh and includes measurements of formant trajectory length and spectral rate of change for the diphthongs (Fox & Jacewicz 2009). The results largely confirm claims about contrastive vowel categories in Northern and Southern Welsh. In contrast to auditory-based accounts, however, pairs of Northern Welsh vowels were found to differ, not only in terms of duration, but also vowel quality. The diphthongs, in turn, revealed interesting cross-dialectal differences in spectral dynamics across their trajectories. The results have implications for notions of contrastivity in languages with large vowel inventories.