I'm planning on eventually building a system for both surround sound and music listening. My budget is small and I plan on beginning with just a couple speakers for music listening and then in the next couple of years adding to the system, building it to surround. What exactly are the differences between an amp and a reciever? To get the same quality sound for music what is the price differential between buying a receiver vs. an amp? Am I better off buying an amp and getting a better receiver later? Right now I would have to buy a lower end receiver, for example a NAD T 743 instead of a 763. Thanks for your help.
By amp do you mean a stereo amp (integrated/separates) or a multichannel power amp or multichannel receiver without radio-tuner?
A couple of years is a long time. Lots of things will change by then, connectors, surround formats, etc. If you are going to use your system mainly for music then I suggest you go and get an integrated stereo amp first.