First of all...note 3 is compatible.with fiio e 17 alpen. The output is from usb port with a standard micro otg usb cable.
The sound in headphones is very clean comparable with s4 or even better.
I'm looking forward for the full review from gsmarena to see the results of audio test but for my ears it's at least even or even better than S4 and a lot better than Xperia Z Ultra.
I own snapdragon version of note 3. My headphones are senn momentum black. The note can,t drive those headphones at full potential but the sound is loud enough for a " normal" person. I like the sound louder, but I could live with the power of the N3 without external amplifier.
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