Hi eveybody, I'm currently working away from home quite a lot and i'm therefore looking for a decent headphone amp / DAC. Currently using an Arcam Rpac, but im pretty sure there will be something better. I'd like to be able to connect to my ipad rather than use a laptop. but im pretty sure all DACs/amps will be bus powered. Im using Sennhesier HD650's which i think the Rpac struggles with, although the sound is really good. Any help would be appreciated. Regards, Mike