Hi
@hqssui. I tested with a full charge last night. Using 320kbps MP3 files, it lasted more than 9.5 hours. I had to terminate the test at 9.5 hours because I was able to head out and cannot monitor it further. At then, the battery indicator was without any bars, but it has been like that at the 8 hour mark too. So about 10 hours seems fair to me.
This was with the balanced PO at volume 25 (out of 100) for my IEMs. Perhaps it will last longer on SE. I did noticed previously that battery seems to drain faster on hi-res files, particularly DSD128 files.
From what I understand, the AK4497 chip is not very energy-efficient (346 mW!). So, I am really happy that it can last > 9.5 hours on MP3 files. More importantly, the sound quality is nice.
@demo-to, Penon Audio is selling this at USD245. I would recommend it over the Shanling M3s, because a Chinese user reviewed that the FA1 made him leave his M3s in the drawer after getting the FA1.
Happy listening!