Hello, i bought this headphones yesterday, and i love his sound, very powerfull sound, but i feel the vocals a little reccesed, I think i need to burn it about 50 hours, How much this headphone improve with burn(50 hours?)?, and a second question, will a fiio e5 improve the sound of this headphones? In what sense? I think i should try beacause they are only 20€.
Don't worry about burn in, just listen to music and it shall seem better with time.
The Fiio e5 in my experience has been quite useless. No difference between it and on-board PC sound output. It does have a bass boost feature though which makes music sound bloated and adds distortion. So yeah, not something I'd recommend; a waste of money on my part.
The E5 provides very little benefit for the Shure 840s and AHT-M50s I have access to. I advise you to a save a little longer and get something that will push them with a bit of authority. (I do like the E5 with my bass-lite IEMs for the artificial bass boost.)