Linner Mercury vs Sennheiser All-Day Clear Slim
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 OTC hearing aid priced at $387, earning a B grade with a SoundScore of 3.0/5 in our lab testing. This visible-in-ear style device ranks #60 of 65 in the OTC Hearing Aid category, positioning it in the lower tier of available options. In our standardized testing, the Mercury demonstrates excellent feedback handling at 4.7/5, scoring 0.16 points above the category average. This means users are unlikely to experience whistling or squealing during typical wear. However, the device shows limitations in other key areas. Speech in quiet scores 2.2/5, falling 0.62 points below the category average, while speech in noise performance is low at 1.0/5, sitting 0.48 points below average. Own-voice comfort is also low at 1.6/5, measuring 0.91 points below the category average. The most significant limitation is music streaming, which scores 0.0/5—a full 1.92 points below the category average. Users who plan to stream phone calls or music through their hearing aids should consider alternatives. At this price point, competitors like the Elehear Beyond and Apple AirPods Pro 2 offer substantially higher overall scores. The Linner Mercury may suit budget-conscious first-time users who prioritize stable, feedback-free wear over streaming capabilities or challenging listening environments. However, those seeking better speech clarity or music quality should explore other options in this price range.
Choice

Sennheiser All-Day Clear Slim
The Sennheiser All-Day Clear Slim is a premium OTC behind-the-ear hearing aid priced at $1,499, earning an A grade with a SoundScore of 4.1/5. This places it in the top 23% of OTC hearing aids tested in our lab, ranking #16 among 65 devices in its category. This device excels in areas that reflect Sennheiser's audio heritage. Music streaming quality is a standout strength, scoring 3.8/5—a solid result that's 1.88 points above the OTC category average. Feedback handling is excellent at 5.0/5, meaning users can expect stability without whistling during typical use. Speech in quiet environments also performs well at 3.6/5, sitting 0.85 points above average for the category. However, the All-Day Clear Slim shows limitations in other areas. Speech in noise scores 1.5/5, matching the category average but representing a low absolute score that may challenge users in noisy restaurants or group conversations. Own-voice comfort is below average at 1.9/5, which could affect how natural users sound to themselves during conversation. The All-Day Clear Slim is best suited for consumers who prioritize music streaming and media consumption alongside hearing support, and who spend more time in quieter environments. Those frequently navigating noisy social situations may want to compare against higher-ranked competitors in this price range, such as the Lucid Tala or Audicus Omni 2, which achieve stronger overall scores.
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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