Abstract
This study compared preferred volume setting for linear peak clipping, compression
limiting, and wide dynamic range compression (WDRC) amplification and quantified speech
audibility at the preferred volume setting for each amplification type. Ten listeners
with mild-to-moderate hearing loss were fitted monaurally with a behind-the-ear hearing
aid programmed sequentially with WDRC, compression limiting, and linear peak clipping
amplification. Speech was presented in quiet and in noise at a range of input levels.
In each condition, the listener adjusted the volume for maximum clarity. Signal levels
were measured using a probe microphone system. There was no significant difference
in speech audibility between amplification strategies for any speech level regardless
of the presence or absence of background noise. These results imply that the improved
audibility advantage of WDRC over linear amplification demonstrated in controlled
environments may not be maintained in situations where the hearing aid wearer controls
the volume.
Abbreviations: AAI = Aided Audibility Index, AI = Articulation Index, ANOVA = analysis of variance,
NAL-R = National Acoustic Laboratories-Revised, SIR = Speech Intelligibility Rating,
WDRC = wide dynamic range compression
Keywords
Amplification - audibility - clarity - preferred volume