MDHearing VoltMax vs Otofonix Groove
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 places it in the lower tier of the OTC hearing aid category, ranking 62nd out of 65 devices tested. In our testing, the VoltMax delivered mixed results across key performance areas. Its standout strength is excellent feedback handling, scoring a perfect 5.0/5—above the category average by 0.46 points. This means users can expect stable performance without whistling or squealing during typical daily activities. However, speech clarity proved challenging, with speech-in-quiet scoring 1.9/5 (0.93 points below category average) and speech-in-noise at 1.0/5 (0.48 points below average). Own-voice comfort measured 2.4/5, slightly below the category norm. A significant limitation is music streaming, which scored 0.0/5—nearly 2 points below the category average. Users who prioritize phone streaming for calls or media should consider alternatives. The device features rechargeable batteries, offering convenience over disposable options. At this price point, several competitors deliver substantially stronger overall performance. The VoltMax may appeal to budget-conscious consumers who primarily need basic amplification with reliable feedback control and don't require streaming capabilities. Those seeking better speech clarity or music streaming should explore higher-scoring options in this price range.

Otofonix Groove
The Otofonix Groove is a behind-the-ear prescription hearing aid priced at $795, earning a C grade with a SoundScore of 2.7/5 in our lab testing. This rechargeable BTE ranks #38 of 39 devices in the prescription hearing aid category, placing it in the bottom 5% of its class. In our testing, the Groove demonstrated excellent feedback handling at 5.0/5, scoring 0.28 points above the category average. This represents a genuine strength, with the device maintaining stability during our standardized challenge motions. However, speech performance was significantly limited, with speech in quiet scoring 1.0/5 (2.40 points below the category average of 3.40) and speech in noise also at 1.0/5 (1.11 points below average). Music streaming was not functional in our tests, scoring 0.0/5 against a category average of 2.76. Own-voice comfort also fell well below typical prescription hearing aid performance at 0.4/5, which is 2.30 points below the category average. At this price point, several lower-cost alternatives delivered stronger overall performance in our testing. Consumers seeking value in the prescription category may want to explore other options, though those requiring robust feedback control in a rechargeable BTE format may find the Groove's stability noteworthy despite its other limitations.
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
Recorded samples (Tuned)
Fitting configuration for tuned fit