You have the 180 watt base system, the only amp is a tiny little one for the sub, it gets its signal from the signal going to the rear speakers and it sits inside a tray that hangs below the stock sub. The rest of the speakers are powered off of the headunit, which means you can replace the headunit and everything should work just fine. The only thing that might not work is the stock sub, but that thing is so shitty anyway you would be better off just unplugging it (and it won't cause the system to fail).