Difference limen for perception of aspiration noise
Rahul Shrivastav, Christine M. Sapienza · The Journal of the Acoustical Society of America · 2003
The relationship between the vocal acoustic signal and the perception of voice quality has been the subject of much research. An increase in the intensity of aspiration noise is associated with a perception of greater breathiness in voices [Klatt and Klatt (1990); Childers (1993)]. Shrivastav (2001) found that subjective ratings of breathiness could be better predicted using measures calculated from an auditory spectrum of the vocal acoustic signal. These measures were found to vary with changes in the spectral slope as well as the intensity of aspiration noise in voice. The aim of the present experiment was to determine the smallest change in the intensity of aspiration noise that could be perceived by listeners. Six voice continua, with increasing intensity of aspiration noise, were generated using the Klatt synthesizer. Five listeners participated in an adaptive listening test, where these stimuli were presented in pairs and listeners were asked to identify the stimuli in each pair as being same or different. Listener responses were used to determine the difference limen for changes in intensity of aspiration noise in voice. These findings will help understand the perception of breathy voice quality and to develop objective measures for its quantification.