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

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.
Choice

Phonak Sphere Infinio
The Phonak Sphere Infinio is a premium prescription behind-the-ear hearing aid released in 2024, priced at $4,898. In HearAdvisor's lab testing, it achieved a SoundScore of 5.0/5 and an A grade, ranking #1 among 36 prescription hearing aids tested. This device delivers exceptional speech performance, particularly in challenging listening environments. Speech in noise scored an excellent 4.7/5, measuring 2.74 points above the category average—a substantial margin that sets it apart from competitors. Speech in quiet also performed strongly at 4.5/5, sitting 1.15 points above average. Music streaming earned a strong 4.0/5, exceeding the category average by 1.36 points. The Sphere Infinio does show some trade-offs. Feedback handling scored a solid 3.6/5 in absolute terms, though this falls 1.11 points below the category average of 4.71/5. Own-voice comfort scored a mixed 2.3/5, slightly below the category average. These are areas where some competing premium devices perform better. This hearing aid is best suited for those who prioritize speech clarity, especially in noisy environments like restaurants or social gatherings. The behind-the-ear style offers rechargeable batteries and streaming compatibility with both iPhone and Android devices. Among premium-priced competitors like the Oticon Intent (4.85/5) and Oticon Real (4.75/5), the Sphere Infinio leads in overall sound performance, earning HearAdvisor's Expert's Choice Award for 2024 and 2023.
We independently review each item we recommend and appreciate your trust and support. When you buy through our links, we may earn a commission. Learn More.
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