I have a 2001 a4 and it has the audi symphony head unit with the bose speakers (2 tweeters and 2 mids up front, 2 mids and 2 "subs" in the back) but i was lookin around for the stock amp the other day, because i'm considering adding a sub, and i couldn't find the stock amp. is it possible that the person before me took it out and hooked everything stright to the head unit because maybe they used a different amp like a normal head unit in a normal car or is this not possible in our cars to do that because of the bose system? i know the amp is supposed to be in the trunk on the left side so mayb it got moved or relocated sumwhere else in the back? i dunno, any help would be greatly appreciated though. thanks a tonnnn.[&:]