I've used a few different music players with these headphones. The first one was the iPod Video, this was a lovely gift from a friend and at that time I didn't really know about lossless music but I did always rip CDs at 320kbps into mp3s, so that worked when I was out and about but it was plugged into my computer more than the iPod.

Had an iTouch for just a few months, it didn't last as iTunes was nothing but bloatware and no flac support.

The second player I bought (in 2011) was a nice jump up, it was a HiFiMan HM-601. At this point I found about flac and it was much nicer to load music on an SD card rather than through a proxy program. The first music I ripped to flac and played on this player was Daft Punk - Discovery and it was amazing. The HM-601 has a built-in headphone amp and my ears were ruined forever to this new standard of listening.

Most other times I have these headphones plugged into computer playing games mostly and while the internal amp of the HM-601 had spoiled me I was no longer satisfied with the built-in sound cards on most motherboards. Did some poking around and found the ASUS Xonar Essence STX has a dedicated headphone amp! Also it doesn't do any fake 7.1 surround in stero headphones (which a lot of gamer audio gear tried to pull off. Badly). It was just stereo sound and did it very well.

While the HM-601 is a decent player I found myself not liking it's clunky menu system, lack of album art support and other little nit picky details. However I was quick to find the Fiio X5, it took me a while to splurge on buying it as it breaks the cost of what I normally feel comfortable spending on audio gear of any sort. After reading what could be considered the 100th review I felt at ease as it had everything. Compared to my headphones it's very new, bought it in Sept 2014 but so far it's doing everything I wanted and more.