Third International Conference on Spoken Language Processing (ICSLP 94)
"Controllability" is defined as the ability to produce desirable pitch, intensity and timbre according to the speaker's intention. As one component of the "controllability", the ability to keep the vocal fundamental frequency, F0, and intensity as constant and as close to a target as possible when instructed to produce a sustained vowel was tested. Using an object oriented acoustic analysis system, magnitude of the slow and fast fluctuations in F0, fractal characteristics and some other voice-quality-related parameters were analyzed for singing, normal/modal and pathological voices. All the pathological groups showed larger variations in F0, or lower controllability, than the normal controls. The ability to keep vocal F0 and intensity as constant as possible was dependent on the target conditions which speakers intended to produce particularly for the neurological disorder patients. These results suggest that vocal controllability can be assessed quantitatively by the method proposed.
Bibliographic reference. Imaizumi, Satoshi / Abdoerrachman, Hartono / Niimi, Seiji. (1994): "Controllability of voice quality: evidence from physiological and acoustic observations", In ICSLP-1994, 1467-1470.