I'm a total noob when it comes to anything related to audio... up until recently I never even knew about amp's aside from the fact that you needed to plug an electric guitar into one to get sound. 
Anyways, with that in mind, I'm trying to get into some nice sounding audio by buying a decent set of cans now and upgrading later on down the line. I'll probably be getting something like the HD25's or the M50's to start with.
On the subject of an amp, would a Yamaha HTR-5640 theater receiver work? What would it be comparable to in the realm of dedicated amps?
Also, I'm confused as to what a DAC is and what the parts of a source are (Amp + DAC?).
How would I go about hooking up the HTR-5640 to my Macbook Pro in the first place?
Here is the Yamaha page on the receiver: http://www.yamaha.com/yec/products/productdetail.html?CNTID=200185&CTID=5000400
Thanks a lot! Again, I have no knowledge about anything audio related so I need everything explained.
