Originally Posted by kkcc
Em... Don't ever had much heat issue with my Note 2. Probably not high-end enough!
The 901 is hot enough just on standard amp board with 45mins of play time (not charging) that I don't feel comfortable with it in my pants, and I haven't really felt why the AK120 is facing an "uphill battle" based on what I'm hearing now. ow. Of course we all hear differently. Care to share your impressions?
The Note 2 is a ridiculously enormous phablet, of course it can dissipate heat much easier with more surface area. It has a huge battery that can run cooler because it has less stressful power drain, and more surface area to dissipate heat. Just as the HM-901 gets hotter quicker than the larger HM-801. Seems the heat is primarily from the battery as far as I can tell, as the back panel is the hottest.
Everyone bitched about the HM-801 being too big. Now the smaller HM-901 has to do more in less space. Maybe someone can make a large aluminum heat sink case for the HM-901 and make it larger than the HM-801 in the end.
I have not heard the AK120, but will have a chance very soon. (In about a week). The AK120 is facing an uphill battle because it's using a low powered DAC meant for portable use, and is a very common chipset in use in many products already, and is honestly not on the same level as the ESS Sabre 9018 DAC chipset. The AK120 is a nice evolutionary upgrade from the AK100, so I'm not expecting it to be night and day difference in sound quality, but rather a refinement and subtle upgrade.
The HM-901 is completely different from the HM-801, pretty much from the ground up. Totally different DAC chips, volume control and amp structure, and the OS / UI is completely different as well. The only feature the HM-901 shares in common with the HM-801 is using over the top, non-portable designed components in as small a battery powered package as possible. No one else if accomplishing this feat.
I appreciate the slick and compact industrial design of the iRiver AK100 and AK120. But, in the end, at it's core, it's based on a lower quality DAC that makes compromises for battery life, and compactness.
The HM-801 and HM-901 made no compromises for sound quality, but that came at the expense of battery life, more heat, and larger size. Don't get me wrong, a lot of people would love to have a high end DAC shoehorned into a box as small as the AK120. Sure. But who would want to deal with a DAP that you can only use for 20 minutes, because it would overheat or run out of batteries first?