A Prediction Method for Listening Score and Speech Audibility Taking Account of Hearing Loss due to Aging under Fluctuating Noise

Abstract

The authors propose a method for estimating and/or predicting the listening score and psychological impression of speech audibility taking into account an effect of the hearing loss due to aging under fluctuating noise. In a real acoustic environment in which audio signals are transmitted and listened to, both the sound pressure level and the frequency component of the noise show an irregular fluctuation over time. Taking the above into consideration, the index of I which reflects the mutual relationships between the spectrum level of the speech peaks and that of the noise within a short time scale, is introduced. Prediction accuracy of I is estimated, regarding how the listening score and psychological impression of speech audibility change in the case of listening to monosyllables under an actual noise environment. The predicted results are in good agreement with the observed values from psychological listening experiment that both the audio signal and the noise which passed through frequency filters simulating hearing loss due to aging are transmitted to subjects with normal hearing.