noustuffthe short answer is yes. look around on the the forums but most agree that the cans will sound weak at best w/o an amp. I'm running an old HeadRoom Micro Amp with the AKG K702 and I love the detail. But, I'm still thinking about this deal.
noustuffRecommended, but not required per se. At 60+ ohms you'll definitely benefit from something like the SMSL SD793II or the Bravo Audio Ocean if you want to do tubes. It'll be clearer than onboard audio.