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Product Comparison

Cearvol Diamond X1 vs Phonak Audéo EON Sphere

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

Uses Official HearAdvisor Lab Data
Cearvol Diamond X1 Hero
CearvolSoundGrade B

Cearvol Diamond X1

The Cearvol Diamond X1 is a budget-priced OTC hearing aid available for $199, earning a B grade with a SoundScore of 3.7/5 in our lab testing. This visible-in-ear style device ranks #30 among 65 OTC hearing aids tested, placing it in the top 45% of its category. The Diamond X1 delivers a mixed performance profile with one notable strength: music streaming. With a score of 4.1/5, it performs 2.18 points above the category average—a substantial margin that makes it appealing for users who value audio entertainment through their hearing aids. Feedback handling is excellent at 4.5/5, providing stable performance during typical daily movements. Both iPhone and Android streaming are supported with rechargeable batteries for convenience. Speech performance presents a more modest picture. Speech in quiet scores 2.8/5, which is above the category average but only mixed in absolute terms. Speech in noise measures 1.7/5—above the category average of 1.48/5, though still low overall. Own-voice comfort is a weakness at 1.7/5, falling 0.81 points below the category average, which may cause your own voice to sound unnatural or boomy. The Diamond X1 is best suited for budget-conscious consumers who prioritize music and media streaming over maximum speech clarity. Those seeking stronger speech performance in challenging listening environments may want to consider higher-scoring alternatives in this price range, such as the Elehear Beyond or Apple AirPods Pro 2.

Expert Choice
Expert
Choice
Product Image
PhonakSoundGrade A

Phonak Audéo EON Sphere

The Phonak Audéo EON Sphere is a premium behind-the-ear prescription hearing aid priced at $4,398. In HearAdvisor's lab testing, it earned a SoundScore of 5.0/5 and an A grade, placing it among the top performers in the prescription hearing aid category. Speech performance stands out as this device's greatest strength. Speech in noise scored an excellent 4.5/5, a full 2.53 points above the category average of 1.96/5—a substantial margin that makes this one of the strongest performers in challenging listening environments. Speech in quiet also performed well at 4.3/5, nearly a full point above the category average. These results suggest the Audéo EON Sphere may be particularly well-suited for users who frequently encounter noisy social settings or group conversations. Music streaming delivered a solid 3.7/5, more than a point above the category average of 2.64/5, indicating above-average audio fidelity for phone-streamed content. Own-voice comfort scored 2.8/5, which sits just above the category average but reflects mixed absolute performance—users sensitive to occlusion effects should discuss this with their hearing care provider. Feedback handling scored an excellent 4.6/5 in absolute terms, though it lands slightly below the category average of 4.71/5. The Audéo EON Sphere represents Phonak's latest premium technology and delivers strong results across most metrics in our standardized testing. It's best suited for users prioritizing speech clarity in difficult listening situations who are prepared for the premium price point.

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Performance metrics

Scale 1-5 (Tuned)

Lab metric by fit

Scale 1-5 (Tuned)

Speech in quietNew
Cearvol Diamond X12.8
Phonak Audéo EON Sphere 4.3
Speech in noiseNew
Cearvol Diamond X11.7
Phonak Audéo EON Sphere 4.5
Own voice
Cearvol Diamond X11.7
Phonak Audéo EON Sphere 2.8
Feedback handling
Cearvol Diamond X14.5
Phonak Audéo EON Sphere 4.6
Music streaming
Cearvol Diamond X14.1
Phonak Audéo EON Sphere 3.7
Overall fit score
Cearvol Diamond X13.9
Phonak Audéo EON Sphere 5.2

Speech level

Adjust input dB (Tuned)

Amplification (REIG)

Insertion gain at 65 dB (Tuned)

Fitting configuration for tuned fit

Cearvol Diamond X1Phonak Audéo EON Sphere
Ear CouplingClosed Dome
Ear CouplingEasyGuard Vented
Receiver
ReceiverMedium-power
Fitting Formula
Fitting FormulaAdaptive Phonak Digital 4.0 (Manufacturer proprietary targets)
Listening Program
Listening ProgramAutoSense OS (Automatic)
Volume Setting
Volume SettingAdjusted to match NAL-NL2 targets at 55, 65, and 75 dB SPL
Tuning Adjustments
Tuning AdjustmentsProgrammed to N3 audiogram, Feedback calibrated, Long-Term Experienced User, Other settings at manufacturer defaults