Developing a single comparison stimulus for matching breathy voice quality
Journal of Speech, Language, and Hearing Research, 55, 639-647, April 2012
Sona M. Patel, Ph.D.
Department of Speech-Language Pathology
Dr. Rahul Shrivastav, Dr. David A Eddins
In this experiment, a single comparison stimulus was
developed as a reference in a perceptual matching task for the
quantification of breathy voice quality. Perceptual judgments of a set
of synthetic voice samples were compared to previous data obtained using
multiple comparison stimuli “customized” for different voices (Patel,
Shrivastav, & Eddins, 2010).
Method: Five male and 5 female samples of the vowel /a/ were selected
from the Kay Elemetrics Disordered Voice Database and resynthesized
using a Klatt synthesizer. Eleven samples were created for each base
voice by manipulating the aspiration noise level. Five samples from each
continuum were evaluated in a perceptual matching task in which a
single sawtooth and noise comparison stimulus was used to obtain
breathiness judgments. Linear regression was used to compare
measurements obtained using the new comparison stimulus against the
customized comparison stimuli.
Results: Results indicated that the noncustomized sawtooth comparison
provides reliability and perceptual distances between stimuli similar
to those obtained using customized comparison stimuli.
Conclusion: A single-variable matching task using a single comparison
stimulus can be used to obtain perceptual estimates of breathiness
across voices and experiments in a laboratory setting. This technique
will help develop models of voice-quality perception.