The effects of vowel, pitch, and dynamics on the emotional characteristics of mezzo-soprano, countertenor, and baritone voices

Previous research on the soprano, alto, tenor, and bass voices have shown that their emotional characteristics change with different vowel, pitch, and dynamics. This work continues the investigation with the mezzo-soprano, countertenor, and baritone voices. Listening tests were conducted whereby listeners gave absolute judgements on the voice tones over ten emotional categories, with the data analyzed using logistic regression. High-arousal categories were stronger for loud tones, whereas low-arousal categories were stronger for soft tones. The categories Happy, Heroic, Romantic, and Comic had an upward trend across the pitch range, whereas Calm, Mysterious, Shy, and Sad had a downward trend. Angry and Scary had different trends among the voices. For most categories, all five vowels were mostly similar in terms of emotional expressiveness, with exceptional cases for the baritone voice. Overall, pitch had the strongest effect and was almost twice as strong as dynamics and vowel, with dynamics slightly stronger than vowel. Vowel O had the largest strength-of-expressiveness overall, closely followed by vowels U and A, and finally vowels I and E last. These results give a quantified preliminary perspective on how vowel, pitch, and dynamics shape emotional expression in the voices across a wide range of voice types.