I want to upgrade my Tiida's stock audio system to something better. I currently have 4 door Speakerss with a 6 cd changer with FM/AM radio and AUX input. I am not sure if I have a built in subwoofer but my guess is that I don't. I want to get new speakers, MAYBE a new head unit (can I use my Tiida's stock head unit?), amplifier(s) and subwoofer. Can someone please suggest me the ideal set up for my car, along with the brand of speakers, HU, amps and subs that I should be looking at? My budget is $600 including wiring. The type of music I listen to is House, Dance, Techno, Rock, Hip-hop/Rap, Alternative and Lounge. I also like to hear the big boom of the bass so I was thinking of a JL Audio subwoofer but don't know which one. Please help.