Need Some DAC + Headphone Advice

Hi Folks:

I have a friend who would like to move into two channel audio via a headphone system. For the moment we are thinking about a DAC/Headphone amp using his laptop music files as a source. He is now sampling headphones but will probably end up with a pair of Sennheiser HD650s. Once his daughter vacates for college he is planning to take over her room over the garage and build a two channel system. Therefore, another approach would be to go for a integrated, preamp or CD player that has a good headphone amp built in so that he can use either once he goes to the larger system. He is a musician so sound quality is key thus the headphone amp + DAC is probably the best route. Price range is around $500 for the DAC/Headphone amp or $1k for either a integrate, preamp or cd player with a headphone amp built in. Suggestions are appreciated.