I am going to be purchasing a pair of HD650s soon and am in need of a new amp for my laptop setup. Currently I am using an Arcam rPAC with my K702s-and they sound pretty darn good in conjunction with each other. However, the rPAC (I have heard some say it is not enough; I will be testing my friend's HD600s with it fairly soon, so I will see how the two pair anyway) is made for lower impedance headphones, so the HD650 definitely is not in its rotation. And so I ask for recommendations on my next amp.
Use: Quiet areas of school, going laptop->rPAC as a DAC->amp, to be determined->HD650s
Music: Classical, rock, jazz, alternative, swing
Price range: preferably under $500 USD