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

iBstone AuraLink
The iBstone AuraLink is a mid-priced OTC hearing aid released in 2024, earning a B grade with a SoundScore of 3.6/5 in HearAdvisor's lab testing. This behind-the-ear device ranks #33 among 65 tested OTC hearing aids, placing it in the top 49% of its category. In our testing, the AuraLink shows a distinctive performance profile with notable strengths in audio entertainment. Music streaming scored a solid 3.6/5, measuring 1.68 points above the category average—a standout result for an OTC device. Feedback handling earned an excellent 5.0/5, sitting 0.46 points above average, meaning users should experience minimal whistling during daily wear. However, speech clarity presents a different picture. Speech in quiet scored a mixed 2.3/5, falling 0.47 points below the category average of 2.79. Speech in noise performance was low at 1.0/5, trailing the already modest category average by 0.48 points. Own-voice comfort scored 2.7/5, slightly above average but only mixed in absolute terms. At $649, the AuraLink faces competition from alternatives offering similar or better sound performance at lower prices, including the iHear MatriX and Olive Union Max. The AuraLink may appeal to users who prioritize music and media streaming over speech enhancement, but those seeking stronger speech clarity should explore other options in this price range.

MDHearing VoltMax
The MDHearing VoltMax is a behind-the-ear OTC hearing aid priced at $699, earning a B grade with a SoundScore of 3.0/5 in our lab testing. This mid-priced device ranks #62 of 65 in the OTC Hearing Aid category, placing it in the bottom portion of tested products. In our standardized testing, the VoltMax demonstrates excellent feedback handling at 5.0/5, scoring 0.46 points above the category average. This means users are unlikely to experience whistling or squealing during typical wear. However, speech performance presents significant challenges—speech in quiet scores a low 1.9/5 (0.93 points below average), while speech in noise scores 1.0/5 (0.48 points below average). These results suggest limited benefit for understanding conversation in both calm and challenging listening environments. Music streaming is a notable weakness, scoring 0.0/5 and falling 1.92 points below the category average. Users who prioritize streaming audio content from their phones should consider alternatives. Own-voice comfort is mixed at 2.4/5, roughly matching the category average. At this price point, several alternatives offer substantially stronger performance. Devices like the Yeasound RIC800 and Sony CRE-E10 score above 4.5/5 at similar or lower prices. The VoltMax may appeal to users who prioritize feedback-free wear and basic amplification with rechargeable convenience, but those seeking stronger speech clarity should explore higher-performing options in this price range.
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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)
Audio scenes
Using MUSHRA scenes (Tuned)
Fitting configuration for tuned fit