The effect of speech melody on voice quality

This paper explores whether a speaker's voice quality, defined as the perceived timbre of someone's speech, changes as a function of variation in speech melody. Analyses are based on several productions of the vowel ‘a', provided with different intonation patterns. It appears that in general fundamental frequency covaries with the ‘strength relationship' between the first two harmonics (H1–H2). That relationship determines the voice quality to some extent, and is often claimed to reflect open quotient. However, correlating the H1–H2 measure to parameters of the LF-model reveals that both the open quotient and the skewness of the glottal pulse have an impact on the lower part of the harmonic spectrum