You are sure you don't need a DAC right? Some people don't realize that they might
Are you going for mainly portability or desktop or just both or whatever.
The E11 is known to be one of the best sounding amps by FiiO. There are reviews on iBasso D-Zero's and what not on HeadFonia but Mike the reviewer likes mids better and so he liked the E10 he compared it too
basically the E10 beats the E7 and D-Zero in sound and the E11 beats the E10 in overal sound. The others have more features to them, but since u mentioned and am willing to get an E11, i'm betting u just need the amp right?
The ZO2 was also a good choice i was looking at. Up to you i guess.
"There have been many questions asked about the Digizoid Zo vs <insert a portable amplifier here>, and the fact is that it’s hard for me to make that comparison. If I was talking about two portable amps, I can make comments about one being dark, having wider soundstage, more bass, etc. But the selling point of the Zo, I believe is the SoundVektor and the adjustable contours, both of which are not available in any portable amps I know. The SoundVektor works and so is the adjustable contours.
On the other hand, if I was talking purely amplifier performance, surely something like the Alpen is simply better. You get better detail level, more frequency extension top and bottom, better articulation, better soundstage width/depth/image and so on. But then I can only make that comparison based on the amplifier performance, not Z02 vs Alpen as complete products."
That was the ZO2 versus the E17 which is extremely similar(through Mike and ClieOS's review) to the E11. so yeah. The PA2V2 is also a challenger but from my research(i was thinking of getting it) the bass isn't as tight as the E11 or FiiO products