True, but I did change just the speakers before changing the entire system. Of course, the new head unit, wiring, amps, and speakers sound great!!

Tone is right about the sub... I am ok with the amount of bass I get from my system, but would consider a sub someday. This may be what you are looking for and a good option to say the least. You'll need an amp... nothing large, just something to power the sub only.

If you are interested in checking to see what new speakers sound like, and you want to put them in yourself, you may be able to purchase some new 5.25"s from say Best Buy or Circuit City, install them and check them out. If you decide not to keep them, uninstall them, box them up, and return them (keeping them in perfect shape of course).

I have a pair of Rockford Fosgate 6.5"s packed away somewhere that I purchased and decided not to use. I'll see if I can dig them up if you are interested.