"Computer, Test My Hearing": Accurate Speech Audiometry with Smart Speakers

Speech audiometry based on matrix sentence tests is an important diagnostic tool for hearing impairment and fitting of hearing aids. This paper introduces a self-conducted measurement for estimating the speech reception threshold (SRT) of a subject, i.e., the signal-to-noise ratio corresponding to 50% intelligibility, based on a smart speaker. While the original measurement procedure is well-evaluated and provides a very high measurement accuracy (< 1 dB test-retest standard deviation), the measurement using a smart speaker differs in several aspects from the commercially available implementation, such as missing control over the absolute presentation level, mode of presentation (headphones vs. loudspeaker), potential errors from the automated response logging, and influence from room acoustics. The SRT measurement accuracy is evaluated with six normal-hearing subjects conducted with an Amazon Alexa application on an Echo Plus loudspeaker in a quiet office environment. We found a significant difference of 0.6 dB in SRT between the proposed and the commercially available testing procedure. However, this bias is smaller than the inter-subject standard deviation, and the measurement accuracy is similar to the original test for normal-hearing listeners, which indicates that smart speakers may become a helpful addition for the screening of hearing deficits.