What amp would any of you recommend pairing these with? I was thinking about a Bottlehead Crack - or maybe a Bottlehead Quicksand, though I don't think a lot of people have heard it yet, for obvious reasons. Maybe a Little Dot MK III. Realistically, I would probably just pick an Objective2 amp since I want something that doesn't color the sound. But what would a good alternative be if I wanted a more rich, warm sound? Something I could use to toy around with the sound signature?
If you wanted a bottlehead amp, I think the S.E.X. is more what you would be looking for(http://bottlehead.com/s-e-x-2-1-specs/). The crack is more for high impedance phones. I'm not sure any of the Little Dot amps are particularly well suited to drive the HE-500, besides maybe the higher end models, I think the LD2 and 3 are both again for higher impedence phones generally. They're kind of low profile amps so I haven't seen a whole lot of people talking about their synergy. My experience with the LD amp has been positive but it is for sure not a first choice.