Voice quality influences acceptable noise levels in adults with normal hearing and hearing loss: introducing the signal degradation degree

The study aimed to measure the effect of speaker voice quality on acceptable noise level (ANL) and to introduce the Signal Degradation Degree (SDD) to quantify within-listener sensitivity to voice-related signal degradation.

Voice quality significantly influences ANL scores; audiologists using ANL testing should be aware that speaker voice quality is a variable that can affect results, and the proposed SDD metric may eventually help standardize within-listener variability measurement — but further validation is needed before adopting SDD clinically.

Identifying voice quality as a meaningful variable in ANL testing challenges the assumption that ANL is a stable listener trait, with implications for how clinicians interpret test results and counsel patients on background-noise tolerance.

1. 01Speaker voice quality significantly affects acceptable noise level (ANL) scores in both normal-hearing and hearing-impaired adults.
2. 02A new metric, Signal Degradation Degree (SDD), is introduced to quantify within-listener ANL variability.
3. 03Study included adults with both normal hearing and hearing loss, broadening generalizability.
4. 04Published in International Journal of Audiology (2026).
5. 05Findings suggest ANL may be less stable as a listener trait than previously assumed.

PMID

42493476

DOI

10.1080/14992027.2026.2704324.

Journal

International Journal of Audiology

Publication type

research_article

Evidence level

2b

Population

Adults with normal hearing and adults with hearing loss

Intervention

Assessment of acceptable noise levels (ANL) with varying speaker voice quality conditions

Comparator

Different voice quality conditions within the same listeners