The timing and sequencing of coarticulated non-modal phonation in English and White Hmong

Despite the growing number of studies on the acoustics of non-modal phonation, little is known about how two distinct non-modal phonations can interact acoustically when coarticulated. This study investigates the acoustics of breathy-to-creaky phonation contours in vowels from a production study of native speakers of English and White Hmong. These languages differ in the nature of the non-modal phonation types. In the English corpus, both the breathiness and creakiness are non-contrastive. In the Hmong corpus, the breathiness can be contrastive or a result of coarticulation with a neighboring segment, but the creakiness is always contrastive. The contours were analyzed using the three measures of phonation that were found to best differentiate non-modal from modal phonation in these languages: H1*-H2*, H1*-A1*, and harmonics-to-noise ratio. Results from these measures provide support for the presence of breathy-creaky contours in vowels. The timing and sequencing of the breathy and creaky phonation types are largely dependent on whether they are contrastive, with contrastive non-modal phonation being present during more portions of the vowel than non-modal phonation derived from coarticulation. The acoustic results also provide evidence for simultaneous breathy and creaky phonation types in Hmong. (C) 2011 Elsevier Ltd. All rights reserved.