I might need to replace my factory audio system and wanted to know which set to buy. This is my first time getting into car audio systems so i really don't know what i want. The generals are extreme clarity (JBL?) and that's it. I don't want want strong subs that are going to shake my windows and make me feel as if my heart is about to jump out. My factory BMW subs are great but some more power is welcome. Im surrounded by three bose systems throughout my house and crave that clarity in my car so can you tell me of systems that have extreme sound clarity and good-strong (remember not that heart jumping out feeling) subs. And second, is there anyway that the new sub can just go into the car (where the old sub is) as i don't want to have those subs sitting in the back. Also the total cost (its a 2006 bmw x3). Thank you