I would suggest a Class BD mono amplifier by Rockford Fosgate
Rockford Fosgate T2500-1bdCP ::
Highlights:
Mono subwoofer amplifier
1,500 watts RMS x 1 at 4 ohms (2,500 watts RMS x 1 at 2 ohms)
2,500 watts RMS x 1 at 1 ohm
CEA-2006 compliant
Dynamic Thermal Management cooling...