Excellent review Joe, my feeling exactly. I have long since moved exclusively to the X5 because I can't find fault with its functions or SQ. I think Fiio and many other dap vendors will have a tough road ahead beating the X5. I think it will take Fiio X7 to best itself.
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Wokei
Excellent review man ..me like ...makes me want to get the X5 ...lol
I have both DX90 (had DX50 before) & X5 and reading your review is like reading my own thoughts on them.
Also own the PS500 and think it sounds almost perfect straight out of the X5, but for my LCD2 I still use my PicoPower for (desired) upgrade in SQ...At the moment listening with my (new) 1964ears V6-Stage. Heavenly sound, what a great player!