Linner Mercury vs Sontro Soundwave
Side-by-side HearAdvisor lab results with SoundGrades, expert pick badges, and the same visualizations we use in product reviews.

Linner Mercury
The Linner Mercury is a budget-priced OTC hearing aid that earns a B grade with a SoundScore of 3.1/5 in our lab testing. Priced at $387, it ranks #60 of 65 devices in the OTC Hearing Aid category, placing it in the top 91% of the category. In our testing, the Mercury shows a mixed performance profile. Its standout strength is excellent feedback handling at 4.7/5, which is 0.16 points above the category average—meaning users are unlikely to experience whistling or squealing during normal use. However, speech clarity metrics fall below category norms: speech in quiet scores 2.2/5 (0.62 points below average), and speech in noise scores a low 1.0/5 (0.48 points below average). Own-voice comfort also scores low at 1.6/5, sitting 0.91 points below the category average. Music streaming is a notable weakness, scoring 0.0/5—a full 1.92 points below the category average. Users who prioritize streaming audio from their phone should consider alternatives. The device uses a rechargeable battery and features a visible in-ear design with power dome coupling. At this price point, several competitors offer stronger overall performance. The Linner Mercury may appeal to budget-conscious consumers who prioritize feedback-free operation over speech clarity and streaming quality, but those seeking better speech understanding in challenging environments should explore higher-scoring options in this price range.

Sontro Soundwave
The Sontro Soundwave is a mid-priced OTC hearing aid priced at $849, earning a B grade with a SoundScore of 3.1/5 in HearAdvisor's lab testing. This behind-the-ear device uses disposable batteries and ranks #61 of 65 OTC hearing aids tested, placing it in the top 92% of its category. In our lab testing, the Soundwave shows a notable strength in own-voice comfort, scoring 3.6/5—a solid result that sits 1.09 points above the category average. This suggests users may experience less of the "talking in a barrel" sensation that can occur with some hearing aids. However, the device faces challenges in other key areas. Speech in quiet scores 2.7/5 (mixed, 0.12 points below average), while speech in noise registers at 1.2/5 (low, 0.28 points below average), indicating potential difficulty in challenging listening environments. The most significant limitations appear in music streaming and feedback handling. Music streaming scores 0.0/5, falling 1.92 points below the category average—a notable weakness for users who value audio entertainment. Feedback handling scores 2.5/5, which is 2.04 points below the category average of 4.54/5, suggesting the device may be more prone to whistling issues. At this price point, competitors offer substantially stronger performance. Devices like the Sony CRE-E10 and Lexie B2 Plus deliver significantly higher sound scores in the same price range. The Sontro Soundwave may suit those prioritizing own-voice comfort over speech clarity and streaming quality, but most users would benefit from exploring higher-performing alternatives at similar or lower prices.
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Performance metrics
Scale 1-5 (Tuned)
Lab metric by fit
Scale 1-5 (Tuned)
Speech level
Adjust input dB (Tuned)
Amplification (REIG)
Insertion gain at 65 dB (Tuned)
Fitting configuration for tuned fit