Basically, I've just bought a Mini saloon that I want some noise in. It has some kenwood 6 or 6.5" speakers (standard size in later cars) in the rear parcel shelf, and I also have an underseat board cut for 6x9's. I'd like some bass, mids and, well general all round good sound. The speakers in the parcel shelf just about make noise loud enough to hear before they distort, and the current 6x9's are just as bad.
Now, do I use both round and 6x9's? Or just 6x9's? I don't really want to use a sub or anything, just want half decent quality sound.
I currently have wires for just 2 speakers, but I guess it won't be too hard to wire in a couple more. The headunit is a half decent sony one.
Maxiumum of about £100-£120
Any help appreciated

Oh, and do I need to run an amp?
Cheers
Dan