Electroacoustic Assessment of Hearing Aids and PSAPs

Hearing aids and personal sound amplification products (PSAPs) are commonly used assistive devices for treating hearing loss. Due to the diversity in the hardware and signal processing algorithms in these devices, comprehensive verification of their performance is essential. Existing standards for assistive hearing devices are primarily used for quality control purposes and do not quantify their performance in a perceptually-relevant manner. This thesis developed a comprehensive electroacoustic testing toolbox for hearing devices that encompasses both quality control and perceptually-relevant measures. In particular, a test sequence was developed to assess the effectiveness of noise reduction feature in assistive hearing devices. Several commercially-available hearing aids and PSAPs on the “best seller” list at Amazon.ca were evaluated using the toolbox. Key results include: (a) hearing aids differ in their noise reduction performance; (b) some of the popular PSAPs do not meet the ANSI standards and are capable of producing dangerous sound pressure levels; and (c) hearing aids performed better than PSAPs on perceptually-relevant metrics