After using the search button extensively I still cannot make up my mind on which to get. which one do you recommend to me? HD600 / HD650 for Trip hop / trance / psy trance

i'm new on this site. i have creative megaworks thx 550= here is specs. http://www.creative.com/products/pro...duct=240&nav=2 i want use with hd 600,also creative 6600 http://www.creative.com/products/pro...duct=465&nav=2 i need an amp.? thanks