I made a few tests with Fiio M15 and IFI BL:
- From a desktop computer with audiophile grade usb out on the motherboard, source Tidal MQA files,Sony MDR Z7 headphones, single ended on IFI, balanced out from Fiio, same Fiio LC 4.4C cable on headphone and with a Fiio adaptor for BL to SE - Ifi sounds better than Fiio, a bigger soundstage and overall a more enjoyable sound, full, with a very deep bass and clarity without harshness. Fiio sounds ok across all frequency range, it is an enjoyable sound but the difference is obvious.
- Fiio as a player on usb out with UAPP player MQA files Tidal, bit perfect mode feeding IFI (led was mangenta ), same MDR Z7 , SE from IFI, BL 4,4 from Fiio - IFI sounds a bit better than Fiio, bigger soundstage and clarity but the difference was not so obvious as before
Then i thought that the main purpose of Fiio is portability, IFI is only transportable but will never fit in a pocket paired with a player or a phone, so instead of MDR Z7 i played the same tracks as before but listening from Fiio FH5 iem and wow ! Fh 5 sounded way better from Fiio than from IFI, very deep lows , very good mids and clarity. Fh5 has a Fiio LC 4.4b balanced cable and the same adaptor for BL to SE. FH 5 from IFI sounded thinner, bass was not so deep as from M15 and the highs were a little too much for my taste. The difference was really big, M15 is better in all aspects than IFI paired with FH5 iems.
First i thought that i did something wrong and repeated the tests,but i obtained the same results, so nothing was wrong.
I guess that the bigger power of IFI makes the difference with MDR Z7 and it will be the desktop solution, while for portability M15 with FH5 is the best sounding solution for me. Let's not forget that M15 is a DAP, it fits easy in every pocket and you don't need anything else while traveling.
In all the other aspects M15 is a very pleasant experience, it has a friendly and fast UI, no glitches so far and a very elegant aspect. I use mainly UAPP in pure mode from Tidal and Neutron for playing files from card, also in my car as a internet player and I enjoy it very much.
Good job Fiio and also hats down for IFi.