Audi stereo upgrade

[sea one]

Salutations to all fellow Audites (or is it Audities?)! This is first post, so pardon my naivete if I do something wrong. Just purchased my four wheel mid life crisis. An '04 S4. After the first week, I'm slowly coming back to Earth. This is my 1st Audi and first manual transmission since a 1992 BMW 320S. What a ball! Glad I went with the car instead of a Harley. Wife was not enthused about two wheels either. This thing is a real sleeper. Not pretentious and very, very discreet. Found that's its very satisfying to toy with younger males driving HO Mustangs. They never realize what hit them! On to my question: only thing I would like to change/upgrade is the factory sound system. Coming from a vehicle that I spent a lot of time in (and money on the audio system), I'm slightly dissappointed in the "symphony" factory unit. Would have preferred the Bose option but not my choice. Has anyone dabbled in keeping the head unit and just upgrading the power side of things? How about component speakers? Any recommendations? Thanks for your help. Looking forward to frequent visits to this website.

Ken