MDHearing Volt 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.

MDHearing Volt
The MDHearing Volt is a budget-priced prescription hearing aid released in 2020, earning a B grade with a SoundScore of 3.0/5 in our lab testing. At $397, it sits in the lowest price tier for prescription devices, ranking #34 of 39 in its category. In our testing, the Volt showed a mixed performance profile with one standout strength: feedback handling scored an excellent 5.0/5, which is 0.28 points above the category average. This means users can expect minimal whistling or squealing during typical wear. However, speech performance was limited, with speech in quiet scoring 1.8/5 (1.65 points below average) and speech in noise at 1.0/5 (1.11 points below average). Own voice comfort was mixed at 2.6/5, roughly matching the category average. Music streaming capability was not functional in our testing, scoring 0.0/5—a significant limitation for users who want to stream audio from their phone. This is 2.76 points below the prescription hearing aid category average. The Volt may appeal to budget-conscious consumers who prioritize basic amplification and feedback-free wear over advanced speech enhancement or streaming features. Those seeking stronger speech performance in the same price range may want to consider alternatives like the RxEars Rxi, which scored 4.07/5 in our testing. The Volt's rechargeable battery and behind-the-ear design offer practical convenience, but its core sound performance reflects its entry-level positioning.
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.
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