Background: Hearing aids amplify low-intensity sounds to make them audible while keeping high-intensity
sounds at an acceptable loudness for listeners with impaired hearing.
Purpose: The purpose of this analysis was to assess loudness and satisfaction at the same
time using a combined loudness and satisfaction questionnaire to rate 18 everyday
environmental sounds.
Research Design: Ten sets of data from four studies, covering three conditions, were analyzed. The
three conditions were unaided, wide dynamic range compression (WDRC), and adaptive
dynamic range optimization (ADRO®). In total, there were 61 subjects giving over 3,000
pairs of ratings for loudness and satisfaction.
Results: The analysis found a strong relationship between loudness and satisfaction ratings
for this set of listeners and conditions. The maximum satisfaction ratings corresponded
to sounds with “comfortable” loudness ratings. Satisfaction was lowest for sounds
that were “uncomfortably loud.” Sounds that were very soft or inaudible also received
low satisfaction ratings unless the sounds were expected to be soft, such as the sound
of one's own breathing.
Conclusions: Hearing aid fittings that place most sounds at a comfortable level are likely to
be more satisfactory than hearing aid fittings that produce more sounds close to hearing
thresholds or discomfort levels. Aided conditions gave higher loudness and satisfaction
ratings than the unaided condition, and the ADRO hearing aids gave significantly higher
satisfaction ratings than the WDRC hearing aids.
Key Words
Comfort - hearing aid - loudness - satisfaction
