If you want dac built in to amp (all in one), likely nothing better for the money than the massdrop THX AAA 789. I think it's right around 500 bucks, but from what I understand it is a lightning quick amp that makes for superb Dynamics.
Otherwise, I would probably get a Schiit modi (DAC) 99 bucks, to go with the JDS Atom (amp) also 99 bucks. No preamp needed since we are talking about headphones not normal 2 channel stereo.
Otherwise, I would probably get a Schiit modi (DAC) 99 bucks, to go with the JDS Atom (amp) also 99 bucks. No preamp needed since we are talking about headphones not normal 2 channel stereo.