AZjake,
As always you will get many good suggestions limited only by our vast differences in personal tastes. That said, I have owned and reviewed many headphone/amp combos and the one I have KEPT (in fact I have TWO of this system- don't ask, I am insane), and which ALWAYS is eminently musical, with plenty of detail, resolution, power and finesse is my Moth Audio S-2A3 amplifier and a set of Sennheiser 650s (or you can use Grado RS-1s but they are much more expensive). The Moth also has the added benefit of being a damn good integrated amplifer you can use with efficient speakers to get terrific sound.
The Moth is built like a freakin tank, can be found used for between $1250 and $1500. The 650s will set you back about $300 and you have money left to buy a Cardas cable for the phones.
Just one of many suggestions.
Good luck in your journey.