Key points are not available for this paper at this time.
The purpose of this research was to test the hypothesis that vocal fry is a separate phonational register: specifically, whether or not the range of fundamental frequencies associated with vocal fry falls below the range of frequencies associated with the modal register. The frequency limits of the modal and falsetto registers, as well as those for vocal fry, were obtained from 12 males and 11 females. The results provide data that demonstrate vocal fry to be a register as specified.
Hollien et al. (Sun,) studied this question.