Comparison of the Aerodynamics of Vocal Fry and Modal Register Phonations

Airflow and subglottic air-pressure recordings were made as ten adult males sustained phonations in the vocal fry and in the low modal registers. Subglottic pressures were obtained from a tracheal puncture and air flow from a pneumotachograph and face mask placed over the mouth and nose. Fry frequencies were measured from an acoustic trace of the phonation, whereas the modal frequencies were the 10% level of each subject's range. Mean vocal-fry fundamental frequency was 29.8 Hz and mean modal frequency was 101.2 Hz. The latter frequencies were produced at the 25% level of the subject's vocal intensity range. Significant differences were not found when comparing subglottic pressures; however, air-flow values in the modal register were higher than those during vocal-fry production.