I don't know if this is the right place to post this. I currently have a HD600 connected to an x-fi titanium HD soundcard and JDS O2 amp. Will I notice an improvement in sound by getting HD 800S with my current setup?

Hello folks, this is a very noob question but I have to ask somewhere. What volume settings should be at what to minimize distortion?   My setup is winamp -> creative titanium HD -> O2 amp -> HD600   should my windows and winamp settings be set to 100% and then control volume only with O2...