Linner Mercury vs Phonak Sphere Infinio
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

Phonak Sphere Infinio
The Phonak Sphere Infinio is a premium behind-the-ear prescription hearing aid released in 2024, priced at $4,898. In our lab testing, it earned an A grade with a SoundScore of 5.0/5, placing it at #2 among 39 prescription hearing aids tested—within the top 3% of its category. The standout performance comes in speech clarity. Speech in noise scores an excellent 4.7/5, a remarkable 2.59 points above the category average of 2.11/5. Speech in quiet also impresses at 4.5/5, sitting 1.07 points above average. For anyone who struggles to follow conversations in restaurants, gatherings, or busy environments, this device delivers measurably superior intelligibility compared to most alternatives we've tested. Music streaming quality is strong at 4.0/5, exceeding the category average by 1.24 points—a meaningful advantage for users who value audio fidelity when streaming from phones. However, own-voice comfort is mixed at 2.3/5, falling 0.40 points below the category average, which may affect how natural your own speech sounds. Feedback handling, while solid in absolute terms at 3.6/5, sits 1.12 points below the category average of 4.72/5. The Sphere Infinio is best suited for users prioritizing exceptional speech understanding, particularly in challenging noise environments, and who are willing to invest at the premium tier. Those especially sensitive to own-voice quality or requiring maximum feedback stability may want to compare alternatives like the similarly-priced Oticon Intent or the lower-priced Phonak Audéo EON Sphere.
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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