Do I really need a pre amp if I buy a power amp with volume controls?

I plan to only hook up the speakers to a cd player. I have seen some power amps with volume controls on them. Will it sound weird without being able to adjust the bass and treble? Do any of you just use a power amp with volume controls that listen to mostly music?

I thought about crown xls 1000 or a samson amp. I heard that even if I find a power amp that doesn't use bare wire that I can buy some kind of adapter to work? I heard that you can buy adapters like that at radio shack. I was going to save up and buy a NAD or Rotel, but the cheaper price on pro amps and watts are drawing me in. Are brands like crown and samson much better then Rotel and NAD? another reason I am concerned a little bit about spending to much is a while back someone tried to break into my house through a window.I noticed that my shed door was open the other day also. I didn't find anything missing though. it;'s making me nervous to spend a lot of money and then get robbed

thank you for all of the help Roger and Walbert. I appreciate it. Do you mean that any brand even the cheaper ones sound okay? I know that certain speaker brands do better with certain receivers because they handle 4ohms. I only have 8ohm speakers. Maybe I am better off with something more basic then expensive like rotel and NAD. Is NAD and Rotel more for people who want to run something difficult like monitor audio, older cerwin vega speakers that are 4ohm b&w magnepan etc? I hear that some receivers have problems powering monitor audio and magnepan.