– Michael Piskor, headfonics.com

“…No question about it, this NuPrime Hi-MDAC has the best build quality in a small form factor DAC that I’ve ever seen…and dang, I own so many and have reviewed so many….
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Our Verdict
Gods honest, I am so tired of the larger DAC’s that claim to be portable but are the size of small bricks. These little DAC’s are the future and I want these companies to push the boundaries of what is possible.
The Hi-mDAC is the first I have heard that is actually very musical, enjoyable on a tonality viewpoint and that offers a slick sense of style in the physical dynamic impact area of the listening experience.
By that, again, I mean it sounds smoother and easier to listen to than most other small DACs. The tradeoff is that it is quite chunky and much bigger than the others, but still, it is petite. And it has decent power! To see a budget tiny DAC performs well with demanding planars such as the Dan Clark Audio Aeon Flow is impressive.
Of course, it does not power it as well as a good desktop amp, but for a casual walk, or sitting outside somewhere, doing the dishes and cleaning the house with this Hi-mDAC in your pocket? I cannot complain when I look at the bigger picture.
We have come far with these little guys and I am happy to keep this in my pocket for the duration of my day, at least, until my phone dies and cannot power the DAC anymore.”

– Guillaume Fourcadier, on-mag.fr

“…The NuPrime Hi-mDAC sound is a great little blend of power and detail, all without getting aggressive. The soundstage is not disproportionate but surprisingly coherent, carried by a rather neutral or even slightly brilliant signature. Unless you come across a monster headset like the Hifiman Susvara or an extremely high impedance headset, the Hi-mDAC can power all headsets or almost without a hitch…”

– NanoTechnos, headfonia.com

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Hi-mDAC achieved something quite remarkable. First and foremost, it drives my Audeze LCD-3 and gives me “commanding bass” as stated on the website. Where the Sennheiser HD-800S felt a little cramped last time, the Audeze sounds quite the opposite with a wide sound-stage and delightful lows….
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The Hi-mDAC is fast and precise, at any level of volume. The layering is impressive, the sound feels natural, effortless and I think NuPrime really did a good job in term of tuning. This isn’t a DAC that’ll wow you right off the batch, on the contrary, the more you’ll listen to it the more you’ll get to love it.
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Tonality
Highs : clean and transparent. The Nuprime achieves a good job there, with a good amount of air. Trebles are precise, never harsh and with the right headphone, you’ll get a level of comfort that I wouldn’t believe possible a few years ago. It’s never dry, never sibilant, never boring. Very impressive!
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Mids : excellent layering and great spaciousness. The mids blends perfectly with the rest of the spectrum. The soundstage is excellent, sometimes astounding until you reach the highest level of volume. If so, the mids tend to fall behind the highs and lows, giving us an odd V-Shap signature. Still, this is only if you really push the DAC to its limit.
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Lows : fast and powerful. Bass is impressive, very impressive. Usually, this is where small DAC falls short, but this is never the case with the m-DAC. It’s fast, powerful and with a good headphone, you’ll be rewarded by deep, tight, toe-tapping bass. Plus side, it never oversteps on the other frequencies…”