Understanding hearing aid sound quality for music-listening

To improve speech intelligibility for individuals with hearing loss, hearing aids amplify speech using gains derived from evidence-based prescriptive methods, in addition to other advanced signal processing mechanisms. While the evidence supports the use of hearing aid signal processing for speech intelligibility, these signal processing adjustments can also be detrimental to hearing aid sound quality, with poor hearing aid sound quality cited as a barrier to device adoption. Poor sound quality is also of concern for music-listening, in which intelligibility is likely not a consideration. A series of electroacoustic and behavioural studies were conducted to study sound quality issues in hearing aids, with a focus on music. An objective sound quality metric was validated for real hearing aid fittings, enabling researchers to predict sound quality impacts of signal processing adjustments. Qualitative interviews with hearing aid user musicians revealed that users’ primary concern was understanding the conductor’s speech during rehearsals, with hearing aid music sound quality issues a secondary concern. However, reported sound quality issues were consistent with music-listening sound quality complaints in the literature. Therefore, follow-up experiments focused on sound quality issues. An examination of different manufacturers’ hearing aids revealed significant music sound quality preferences for some devices over others. Electroacoustic measurements on these devices revealed that bass content varied more between devices than levels in other spectral ranges or nonlinearity, and increased bass levels were most associated with improved sound quality ratings. In a sound quality optimization study, listeners increased the bass and reduced the treble relative to typically-prescribed gains, for both speech and music. However, adjustments were smaller in magnitude for speech compared to music because they were also associated with a decline in speech intelligibility. These findings encourage the increase of bass and reduction of treble to improve hearing aid music sound quality, but only to the degree that speech intelligibility is not compromised. Future research is needed on the prediction of hearing aid music quality, the provision of low-frequency gain in open-fit hearing aids, genre-specific adjustments, hearing aid compression and music, and direct-to-consumer technology

A Qualitative Study of the Effects of Hearing Loss and Hearing Aid Use on Music Perception in Performing Musicians

Hearing aids (HAs) are important for the rehabilitation of individuals with hearing loss. Although the rehabilitation of speech communication is well understood, less attention has been devoted to understanding hearing-impaired instrumentalists’ needs to actively participate in music. Despite efforts to adjust HA settings for music acoustics, there lacks an understanding of instrumentalists’ needs and if those HA adjustments satisfy their needs. Purpose: The purpose of the current study was to explore the challenges that adult HA-wearing instrumentalists face, which prevent them from listening, responding to, and performing music. Research Design: A qualitative methodology was employed with the use of semistructured interviews conducted with adult amateur instrumentalists. Study Sample: Twelve HA users who were amateur ensemble instrumentalists (playing instruments from the percussion, wind, reed, brass, and string families) and between the ages of 55 and 83 years (seven men and five women) provided data for analysis in this study. Amateur in this context was defined as one who engaged mindfully in pursuit of an activity. Data Collection and Analysis: Semistructured interviews were conducted using an open-ended interview guide. Interviews were recorded and transcribed verbatim. Transcripts were analyzed using conventional qualitative content analysis. Results: Three categories emerged from the data: (1) participatory needs, (2) effects of HA use, and (3) effects of hearing loss. Participants primarily used HAs to hear the conductor’s instructions to meaningfully participate in music rehearsals. Effects of HA use fell within two subcategories: HA music sound quality and use of an HA music program. The effects of hearing loss fell within three subcategories: inability to identify missing information, affected music components, and nonauditory music perception strategies. Conclusions: Not surprisingly, hearing-impaired instrumentalists face challenges participating in their music activities. However, although participants articulated ways in which HAs and hearing loss affect music perception, which in turn revealed perspectives toward listening using the auditory system and other sensory systems, the primary motivation for their HA use was the need to hear the conductor’s directions. These findings suggest that providing hearing-impaired instrumentalists access to musical experience via participation should be prioritized above restoring the perception of musical descriptors. Future research is needed with instrumentalists who no longer listen to or perform music because of hearing loss, so that the relationship between musical auditory deficiencies and participation can be better explored