Cearvol Diamond X1 vs HearingAssist Control
Side-by-side HearAdvisor lab results with SoundGrades, expert pick badges, and the same visualizations we use in product reviews.

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.

HearingAssist Control
The HearingAssist Control is a behind-the-ear OTC hearing aid priced at $549, earning a B grade with a SoundScore of 3.3/5 in our lab testing. This places it in the lower portion of the OTC category, ranking #51 of 65 devices tested. In our testing, the Control demonstrates notable strengths in speech performance. Speech in quiet scores 0.59 points above the category average at 3.4/5, representing solid absolute performance. Speech in noise comes in at 2.0/5—above the category average by 0.56 points, though only mixed in absolute terms. Feedback handling is excellent at 5.0/5, meaning the device remained stable without audible squealing during our standardized challenge tests. The device shows significant weaknesses in other areas. Music streaming scored 0.0/5, which is 1.92 points below the category average and indicates this device does not support or perform well with phone audio streaming. Own-voice comfort is also below average at 2.1/5 (0.41 points below category average), which may be noticeable during extended conversations. The HearingAssist Control may suit users who prioritize speech clarity over streaming functionality and who don't require premium sound quality across all use cases. However, buyers in this price range should note that several competitors—including the Yeasound RIC800 and Sony CRE-E10—deliver substantially higher overall scores. Those seeking similar speech performance at a lower cost may also consider the iHear MatriX.
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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