The Hearing-Aid Speech Quality Index (HASQI)

Signal modifications in audio devices such as hearing aids include both nonlinear and linear processing An index is developed for predicting the effects of noise, nonlinear distortion. and linear filtering on speech quality. The index is designed for both normal-hearing and hearing-impaned listeners It starts with a representation of the auditory periphery that incorporates aspects of impaired hearing The cochlear model is followed by the extraction of signal features related to the quality judgments One set of features measures the effects of noise and nonlinear distortion on speech quality, whereas second set of features measures the effects of linear filtering The healing-aid speech quality index (HASQI) is the product of the subindices computed for each of the two sets of features. The models die evaluated by comparing the model predictions with quality judgments made by normal-hearing and hearing-impaired listeners for speech stimuli containing noise. nonlinear distortion, linear processing. and combinations of these signal degradations