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Product Comparison

Cearvol Diamond X1 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.

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
Sennheiser All-Day Clear Slim Hero
SennheiserSoundGrade A

Sennheiser All-Day Clear Slim

The Sennheiser All-Day Clear Slim is a premium behind-the-ear OTC hearing aid priced at $1,499, earning an A grade with a SoundScore of 4.1/5 in our lab testing. This places it in the top 23% of the OTC hearing aid category, ranking #16 among 65 tested devices. In our testing, the All-Day Clear Slim demonstrates notable strengths in music streaming, scoring 3.8/5—a solid result that sits 1.88 points above the category average. This makes it one of the stronger performers for users who prioritize audio quality when streaming from their phone. Feedback handling is excellent at 5.0/5, measuring 0.46 points above the category average, meaning users can expect stable performance without whistling during typical daily activities. Speech clarity in quiet environments is solid at 3.6/5, coming in 0.85 points above the category average. However, speech in noise performance is low at 1.5/5, matching the category average—a common limitation across OTC devices. Own-voice comfort scores 1.9/5, which is 0.61 points below the category average, suggesting some users may notice their own voice sounds different or hollow. The All-Day Clear Slim includes rechargeable batteries and supports streaming to both iPhone and Android devices with hands-free functionality. At its price point, alternatives like the Lucid Tala and Audicus Omni 2 offer higher overall scores, though the Sennheiser may appeal to those who value the brand's audio heritage and prioritize music streaming quality over speech-in-noise performance.

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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
Sennheiser All-Day Clear Slim3.6
Speech in noiseNew
Cearvol Diamond X11.7
Sennheiser All-Day Clear Slim1.5
Own voice
Cearvol Diamond X11.7
Sennheiser All-Day Clear Slim1.9
Feedback handling
Cearvol Diamond X14.5
Sennheiser All-Day Clear Slim5.0
Music streaming
Cearvol Diamond X14.1
Sennheiser All-Day Clear Slim3.8
Overall fit score
Cearvol Diamond X13.9
Sennheiser All-Day Clear Slim4.1

Speech level

Adjust input dB (Tuned)

Amplification (REIG)

Insertion gain at 65 dB (Tuned)

Fitting configuration for tuned fit

Cearvol Diamond X1Sennheiser All-Day Clear Slim
Ear CouplingClosed Dome
Ear CouplingSleeve Closed