I have a 2003 A4 with the Audi Symphony Bose sound system. A factory subwoofer is mounted on the rear deck, and looking at the sub from the trunk, it looks like there is room to mount a second subwoofer next to the stock woofer. I want to stick with the factory head unit and don't need a ton of bass and like having trunk space which is why I'm thinking about getting a second factory Bose subwoofer and trying to mount it next to the origional sub. I'm sure it's possible, I'm just wondering if anyone here has attempted this, and if so, with what results?