Where did you get the HiBy for 685 euros? Here in Spain it is 849 euros!
HiFiGo. They offer multiple shipping options, one of which includes all necessary taxes for EU. (Somehow this does not cost the buyer anything extra. I trust that they know their stuff.)
Share your impressions of it, after it reaches you.
Received it today - quicker than expected. First impressions:
The unboxing was a bit of a letdown. First the entire back-plate came off when I removed the player from the (very snug) foam tray. I guess it's good to know the battery is easy to reach, but I wasn't quite expecting that. Adhesive on the back-plate seemed fine, so I placed it back on and it hasn't come off (or moved) since.
Second letdown - though my own doing - was the pre-applied screen protector. It's one of those two-layer protectors where you pull off the top layer after application. Unfortunately, in my case, this pulled off the entire thing. Will be more careful next time. (There's another protector in the box.)
Beyond that the player has a very nice an premium feel to it. Size is perfect for single-handed operation without compromising on screen real-estate too much.
Comparing to my Sony NW-A105 with DT770 PRO (250) and MDR-1AM2. Disclaimer: I'm not an audiophile by any means. I just really enjoy the light-weight MDR while working and the DT770 for more focused listening.
The most notable difference, especially with the DT770, is the crispness of the HiBy. I'm not sure what the correct articulation is, but it sounds just a tad more "Hi-Fi", bringing you closer to a stage performance feel without having to resort to louder volumes or EQ.
That said, I never disliked the Sony sound and both players let you tweak things to your liking. Primary reasons for switching away from the Sony are its small screen (fine for the built-in Sony player, but unwieldy when using Apple Music or other apps) and lack of volume rotary. (It has 7 little buttons in a row and I too often press wrong when operating it blindly.)
Some other observations:
Android performance is comparable to a low/mid-range phone. Noticeably slower than a flagship, but not annoyingly so. Unless you want to use a ton of non-music apps like you may do on your phone, the performance is absolutely fine.
The LED can get pretty bright in dark environments, but can be turned off.
USB debugging was enabled by default and could only be switched off after enabling Developer Mode.
Audio rate is shown for all apps. The Sony wouldn't, but the HiBy will show me when I hit that (still quite rare) 192K track on Apple Music.
Power usage seems to be very close to what my PC is feeding it, with the battery indicator going both up and down while I'm using it. Will have to try a proper brick.