Originally Posted by bigaudiofanat

The head unit has a pre output that goes to the bose amp. When you take your stock bose head unit amp you need a adapter that can plu into your pre outs and than connect to the harness that goes to the bose amp. Some say well I will jsut bypass the amp. But it is not that simple the bose speakers are 2 ohms so you would blow your new head units built in amp if you hook them up to it. Because the head unit can only support 4 ohm speakers. That is why as of right now if you want to change anything in the bose system you have to change it all. Also even if you did just change the head unit with an adapter the bose system will still analyze and fade out the frequency that it thinks will distort the speakers. Even if you change those speakers to aftermarket the system still thinks they are bose.