Hi. Can anyone recommend a good, cheap amp for my Sennheiser HD 595 headphones? I've been considering the Rega Ear, which has some good write-ups, but I've heard too that it's not so great with low impedance cans (the 595s are just 50 Ohms). Does anyone have any thoughts on how the Rega would go with these phones, or any other suggestions at around the same price? Thanks for your help.