Acoustic characterization of the "pasaggio" in the lyrical voice.

Abstract

The passage between two contiguous vocal registers is called "pasaggio". In lyrical singing, this change should go unnoticed by the listener. Therefore, it should be prepared through the 'voice coverage'. Within the framework of an interdisciplinary research project, the pasaggio was studied in a group of lyrical singers, through measurements with an acoustic camera, sound level meter and accelerometer. We worked with five lyrical singers with academic training and broad experience, each of them with a different vocal register: a soprano, a mezzo-soprano, a countertenor, a tenor and a baritone. Each of them performed a set of a cappella vocal exercises, while the aforementioned measurements were performed at their time; the set of exercises was selected by the singers to meet the objectives of this research. In particular, to study the pasaggio as an acoustic phenomenon, two exercises were particularly interesting: an ascending major scale and a ‘Grand Vocalise’ (a vocalise that covers an interval of an octave plus a fifth). Each exercise was repeated several times by each singer, while accelerometer records were taken on the glottis, sternum, and six points on the head (Mauran's point, nose, mastoid, occipital, eyebrow and 'third eye'). Through the records of the time evolution of sound pressure levels in third octave bands, the acoustic spectra and sonograms, the pasaggio can be clearly visualized. This enables the Song Masters to better explain to their students how to perform the voice coverage and pasaggio, the expected proprioceptions and the acoustic result to be obtained.