Examining the relationship between vowel quality and voice quality

The majority of studies on phonation types have focused on low vowels due to the minimal effects of their first formant on harmonic amplitude. In studies of multiple vowel qualities, reports on the relationship between vowel and voice quality are mixed: some show similar formant frequencies across phonation types (e.g. Abramson, Nye & Luangthongkum 2007, Khan 2012), while others show different formant frequencies depending on voice quality (e.g. Ren 1992, Kuang 2011). Results differ as to whether the degree of non-modal phonation varies (Andruski & Ratliff 2000, Kuang 2011) or does not vary (Esposito 2012, Khan 2012) across different vowel qualities. The present study draws on innovations which allow for more accurate corrections for the effects of formant frequencies on spectral measures (i.e. Hanson 1995, Iseli, Shue & Alwan 2007) to examine the relationship between vowel quality and voice quality, in eight languages – !Xóõ, Burmese, Gujarati, Jalapa de Díaz Mazatec, Mon, Santa Ana del Valle Zapotec, White Hmong, and Yi. While no significant difference in the degree of non-modal phonation due to vowel quality was found, results showed a crosslinguistic pattern in the relationship between vowel quality and voice quality: vowels with higher log (F1) and log (F2) values tended to be produced with creakier phonation, while vowels with lower log (F1) and log (F2) values tended to be produced with breathier phonation, but only on the measure H1*-H2*.