No with the Crack the performance of the T1 is at a different level sonically to the HD650's. The Senns try hard but cannot match the speed, dynamics, neutrality and resolution of the T1's which are at a different level sonically. Considering the price difference this should be expected.
Although there is fantastic synergy with the BHC+HD650 the BHC is actually capable of more sonically than the HD650's can deliver. This is why their are quiet a few T1 and HD800 owners who are very happy with the combination as well.
They both have their own signatures and complement one another each brings its own strengths and flavour I use both phones regularly depending what I plan to listen to. My other half prefers to listen with the HD650's which are great for relaxing with. If you like the HD650's chances are good you will love the T1's, I did.
Its worth noting that both phones can sound very ordinary if not amped properly, but get it right and they are simply an amazing pair of headphones.
Edited by JamieMcC - 2/7/14 at 11:15am