I want a head unit that has an ipod plug in available so i can play my ipod music. A cd player. And two preamp outputs one for my subwoofer amplifier and one for an amplifier for every other component of the system. One question about preamp outputs i have seen 2v and 4v ones but what is the difference? Why would i need a 4v one? Any suggestion or info on head units would be appreciated thanks.
