I guess my refusal thus far to buy a high-def DAP is that despite their software's ability to play hi-def music, none of the hardware beyond the DAC (and even then not always) is capable of besting your standard iPod Touch or iPhone, at least when tested and measured. I guess I'd rather gamble on hi-def music coming to the 6 and new gen of Apple players than spend $800-$2400 on equal (or in some cases inferior) hardware with better software. At least right now. Who knows... If true hi-def music doesn't come to Apple with the new phone announcement, then I might revisit the DAP scenario. But can you imagine if Apple introduces both hi-def music and a Spotify-competitor service? There will be a lot of people walking around with $199 contract phones that (once paired with a decent amp) completely crush the $2400 AK240...
I disagree, because high res files alone don't make better sound. Likewise, neither do regular measurements, such as RMAA, tell you how a device will do playing back complex music under load. Be careful that people are taking measurements just to put down a device. There are quite a few people out there saying "Everything has a flat frequency response, it's all the same/it's a rip-off/whatever." That ain't science, that's abusing facts to be deliberately misleading.
With any kind of test, you need to do it or verify it yourself. Just because someone does a test doesn't mean the results are the absolute truth. It's worth reading the story from Schiit Audio. The last chapter goes into how measurements can easily end up screwed up. A relative of mine has been the editor of various scientific journals for decades and you'd be shocked how many problems there are with research results, ranging from errors and wrong conclusions to outright fraud.
My advice to everyone is: Don't rely on anyone's impressions OR anyone's tests. Go out and try (or test) each device for yourself, with your own music and your own headphones. THAT is the only thing that is going to decide if it is "worth it". Impressions and tests are only data points that may help someone decide if a product is worth checking out.
When I make videos, the reason is not to rant on about how wonderful a product is, it is to give people the chance to see it up close when they may not otherwise be easily able to. It's also a challenge for me to think about why not just I like it or don't like it, but the possible reasons it may be good or not for other people. I think the discussion here from people about the merits or demerits of the different DAPs has been good for the same reasons.
I'll start off by saying I don't consider myself to have tuned ears of a true audiophile, as I haven't been able to demo alot of high quality headphone or IEM's, but I am trying to learn more as I go.
I have had the HiFiMAN HM-901, Sony NW-ZX1, and FiiO X5 paired with my Shure SE846 IEM's. I currently still have the NW-ZX1 and X5. I couldn't live with the size and UI on the HM-901, even though the sound was great with the IEM card. I've got the NW-ZX1 and X5 now and have the same HiRes tracks and ALAC CD rips and MP3 rips on both units. I must say, I do think the X5 does sound better after the first few comparison listens. I like clarity on my highs, and X5 seems to deliver that better than the ZX1. There also seems to be a bit more punch on the low end. The ZX1 sounds very good, but the clarity on the high end doesn't seem to be as crisp as on the X5. However, I will say the UI on the ZX1 blows away the X5, although I could probably live with the X5's UI. The screen on the ZX1 is very nice compared to the previous HiRes players I have owned. I need to pick one of them, as I can't really justify having them both, I also picked up a 5th gen iPod Touch, but as I already have a 7th gen nano and iPad Mini, it is probably going back, as I haven't even opened it yet.
If I didn't have the 2 units side by side, I could definitely live with either of them and be happy. Now the question becomes, is the UI alone worth the $400 premium over the X5...The hard part for me is most of my music is high quality MP3 files ripped by me with EAC, now I rip new CD's I buy into ALAC, but 95% are MP3. I also like the fact that the X5 has a dedicated line output and microusb connection.
I thought there was a bit more clarity with some music with the ZX-1 (all lossless), but definitely not all. I think you nailed it otherwise with the rest of your comments. The Sony has the advantage, with a custom dock, that they can have a dedicated analogue line out as well, which you don't get with micro-USB or a Lightning connection.
I'm looking forward to reading more comparisons from people and comparing them with my own.