Which amp should I choose?

My original amp an mtx jackhammer 1200 watt max got fried due to a leak in my trunk. First I am wondering if my subwoofer is fine and which amp I should now choose. I have one Alpine Type R 12" dual 4 ohm vc. I ordered and tried a boss amp that was 1800 max but it didn't seem to power the sub very much so is it the sub or the crappy boss amp. If it is just the amp please tell me which one I should now choose.