Vowel representation and synthesis of singer identity

Professional singers shape the acoustical attributes of their vocal production to create the perceptual impression of a single instrument spanning a variety of vowel timbres over a wide range of pitch. Samples of the five Italian vowels over a two‐octave range were analyzed using the modal distribution to yield a time‐frequency image of the signal. From such images (high‐order) representations of the composite transfer function of the signal were extracted. These representations provide little evidence for the existence of an acoustic ‘‘signature’’ that is invariant over the singer’s entire range of production. Rather, the data, along with results from a perceptual study, suggest that singers create the impression of a single instrument by smoothly transitioning from one local region of invariance to the next. By identifying these regions, low‐order, perceptually robust approximations are constructed which bear the identity of the singer when used to synthesize new instances of sung vowels. These low‐order representations also serve as endpoints for interpolating between two different singers, as well as boundary points for extrapolating a singer from chest to head modes of production. [Work supported by the MusEn Project at the University of Michigan.]