My friend in China helped me to buy an HM-901 about 4 months back, I was thrilled when I heard it the first time, even bought a pair of Sennheiser IE800 to go with it. Later on I added the balanced amp card together with an RE-600, so I'd be able to use the HM-900 to its full (balanced) potential. Loved the combo, but I felt the sound was not as refined as I hoped and the UI, built quality and industrial left me a lot to desire. So I sold the whole package off after having them for around 2 plus months.
My journey to search for a good portable DAP didn't end there, I started to look for something fancier, the AK120, which is regarded as one of the best portable DAP available. I read a lot reviews and comparison between the HM-901 and AK120, the overall feeling is that HM-901 has slight edge in sound quality even with the standard amp card, but AK120 has much better UI/built quality, and of course it's much smaller and easier to carry around. If not compared with HM-901, most reviews raved about the sound quality of the AK120. I thought I could live with it if its sound quality is somewhere close to HM-901. When I saw a decent deal on a used AK120 about a month ago, I quickly grabbed it.
The AK120 is indeed a very nice little DAP, it can play pretty much anything I put in, DSD too, and the sound quality is super, has great details and resolution when paired w/ high quality IEMs. I tried both IE800 and K3003i with it, both sounded pretty nice. But some how I didn't feel the sound was as attractive as I felt with the HM-901. I didn't have the eager to listen to music with it as much as I hoped, and sometimes I just used my iPhone5 instead, 'cause I didn't feel the AK120 sounded much better. Don't get me wrong, the AK120 is a much better DAP technically than iPone or iPod. It's just I didn't feel its sound very musical at all. Probably that's what many people called 'digital sound'? I felt I enjoyed playing music with my iPhone as much as with the AK120, and iPhone is so much easier to use.
Anyway, ended up my AK120 didn't get much use even I had it by my pillow every day. Yes, I use my portable DAP in house, not on the road. Probably because I drive to work more often than I take public transport. I can live with desktop setup, but I want some flexibility too even when listening to music at home, especially with two young kids around, I can't sit in front of computer for long.
I know portable DAP is always a compromise when comparing with full sized desktop setup. We all have to weight all the factors and see which ones are more important to us. But to me portability isn't the most important factor because I only use it at home. Keeping the AK120 probably defeats its purpose - its great portability. I started to miss the sound of HM-901...
I heard from my friends that later batch HM-901 players have better built quality due to revised moulds and better materials used. So I started to look around and bought another new HM-901 last week directly from Hifiman China. And this time I decided to go with the IEM amp card instead of balanced. My friend brought it over to me a few days ago, upon first listening to my K3003i through the new player, I felt THIS IS IT! That's what I wanted from a portable DAP! The sound is so musical. I had it burnt-in for three days, three nights in a row I couldn't help but listen to music through the new HM901 until after 2am, and the sound got better everyday. I still feel sleepy now when I'm typing this.
Sorry I don't know how to explain or do reviews like those other reviewers, you know, about the highs, mids, lows, sound stage and imaging, layers, or whatever fancy words which some of them I still couldn't figure out what they mean. I just want to say that the sound come out of this HM901 is really musical. Vocals (my favourite genre) sound really sweet, instruments (love the strings and pianos) sound true to what I feel. When I did A/B comparison between the AK120 and HM901, I could feel that the details and resolutions are on par. If I could hear it from the HM901, I could hear it from the AK120. And the same to HM901. But the musics from AK120 just don't sound as attractive as from HM901. In the past a few days, every nights when I lied in bed, I couldn't wait to put my earphones (either K3003 or OMX980) in and switch on the HM901. I never had the same feeling when I had the AK120. The only problem I had in the past a few nights was lack of sleep.
Well, I sold off the AK120 three days after I got the new HM901, don't think I'd look back. For now my search for a good sounding portable DAP ends with the new HM901. The UI is still as unfriendly as before (comparing with iPhone or iPod), even with the newly upgraded firmware. The built quality seems to be slightly better with much improved center wheel, but still no way near the level of AK120. The look is still the same industrial prototype, and it still takes a minute or even longer to boot up. But I am so glad that I got it back whenever I'm listening to my favourite musics with it. This time I won't let it go easily that's for sure.
Just some rants after a long day's work before I go back to the kids. Hope you enjoyed reading them.
Players used: AK120, HM901
Earphones/Headphones used: K3003i, IE800, OMX980, W3000ANV
Sound tracks: various from vocal to classical music
Here are a few quick snaps I had with the players and the IEMs/headphones:
Edited by fengwei007 - 10/8/13 at 5:55am