I am building an audio system for my car. So far, it consists of 2 12" Cerwin Vega DVC's, Kenwood KDC-9017 HU, Adire Revolution Amp. So I have the bass part of my system down. Now I need to worry about the rest of the sound. I want a full system that can be turned up loud and be very high quality. I don't know if I will need another amp for the mids/tweets, because the HU I have has 50x4 watts (supposedly). What amp if any should I get? What speakers do I get? For the speakers, I was thinking of getting this: http://www.sounddomain.com/sku/INFKAPPA605CS I hear that capacitors are useless for this application, would I need to upgrade anything else to successfully use this system? Thanks alot for all of the help!