Physiology and Acoustics of Inspiratory Phonation

Abstract

Summary: Introduction. Inspiratory phonation (IP) means phonating with inspiratory airflow. Some vocalists remarkably master this technique, to such an extent that it offers new dramatic, aesthetic, and functional possibilities in singing specific contemporary music. The present study aims to a better understanding of the physiological backgrounds of IP. Material and methods. A total of 51 inhaling utterances were compared with 61 exhaling utterances in a professional soprano highly skilled in inhaling singing, by means of high-speed single-line scanning and advanced acoustic analysis. Ranges of intensity and Fo were kept similar. Results. The main differences are: (1) an inversion of the mucosal wave, (2) a smaller closed quotient in IP, (3) a larger opening/closing quotient in IP with the additional difference that in IP, the quotient is larger than 1 (opening slower than closing), whereas it is less than 1 in expiratory mode (opening faster than closing), (4) a larger vocal-fold excursion in IP, (5) higher values of adaptive normalized noise energy in IP, and (6) a steeper slope of harmonic peaks in IP. However, jitter values are similar (within normal range), as well as damping ratios and central formant frequencies. The two voicing modes cannot be differentiated by blind listening. Conclusion. The basic physiological mechanisms are comparable in both voicing modes, although with specific differences. IP is actually to be considered as an "extended vocal technique," a term applied to vocalization in art music, which falls outside of traditional classical singing styles, but with remarkable possibilities in skilled vocalists.

The Physics of the Human Vocal Folds as a Biological Oscillator

“…Recently, damping has also been observed during inspiratory phonation [58]: the characteristics seem similar to those of expiratory phonation.…”

Measuring Voice Effects of Vibrato-Free and Ingressive Singing: A Study of Phonation Threshold Pressures

“…She did not report any phonatory discomfort of IP. 5 On the second day of the experiment, after finishing the IP condition, all subjects were asked how long vocal rest they needed, before they felt that their singing voice had totally recovered. One singer reported that no rest at all was needed, two that they would need one hour and one who needed to wait until the following day.…”