An utter disappointment
Crutchfield Customer Review (What's this?)
I had high hopes for this DAP as a low-cost alternative to the pricey Astell&Kern AK100. But I was in for a bitter disappointment. From the onset the build quality looked rather cheap. When connecting a pair of very sensitive and efficient Grado SR225i headphones there was obvious hissing noise (similar to static) on the right channel, even though I was using several high-quality 16bit FLAC recordings of classical music. More generally, the audio performance was subpar, even when compared to a simple Rockboxed iPod. I'm suspecting that the trouble came from the high-impedance HM-601 (at 32 Ohm) and the low-impedance SR225i (at 32 Ohm), causing unnecessary sound-distortion, although I'm not ruling out systemic hardware/software issues. As for the software, HM-601 hangs when trying to play 24bit/88kHz FLAC files. It seems that in the high-resolution FLAC department, it is only capable of playing only 24bit/96kHz, but not much else in my experience. So unfortunately I had to return the item. If you want to pair the HM-601 with Grado headphones, don't even bother. If you have a pair of high-impedance phones (my guess would be above 50-60 Ohm) then I guess the HM-601 is worth a try (after all, there are positive reviews for this DAP online), assuming that you're OK with the software issues described above. For those looking for a less pricey alternative to the Astell&Kern AK100, however, there are other low-cost but high-quality DAP solutions available.
Pros: None that I can think of.
Cons: Hissing noise on Grado headphones. Subpar audio performance with low-impedance headphones. Missing support for some FLAC resolutions (e.g. 24bit/88kHz), causing software freezes.