Spectral correlates of breathiness and roughness for different types of vowel fragments

Breathiness and roughness ratings were related to a number of spectral parameters, including, among others, the relative peak level of the first harmonic, Harmonics-toNoise Ratios (HNR) in selected frequency bands, and level differences between these frequency bands. Analyses were performed for 200 ms vowel onset fragments, 200 ms mid-vowel (post-onset) fragments, and 1000 ms fragments covering both the onset and post-onset parts of a vowel. HNR in the main energy frequency band was the best single predictor of both breathiness and roughness, explaining up to 55% of the variance. A combination of predictors explained 70% of the breathiness variance for all three types of fragments. For the roughness data, the same combination of predictors explained most of the variance in vowel onset fragments (61%), and least in post-onset fragments (35%). Thus, the onset seems to contain more acoustic information relevant to the perception of roughness than the mid-vowel fragment.