The 75 pound QSC RMX5050 is the logical next step to fully realize the potential of the AXIS. It will produce about 4000 watts bridged mono into a 4 ohm load, 20Hz-20,000Hz. It is about $1600.
http://www.zzounds.com/item--QSCRMX5050
If you order this amplifier, please confirm by phone that you are getting the 120VAC version. There is also a 220VAC version.
Did you really think a mere 2000 watts was going to cut it with that monster?
Please note that you will need a dedicated high current wiring for this product. I would suggest a minimum of 10AWG dedicated circuit from the breaker box with a 20A breaker. While the circuit will not handle continuous output at full power, it will be fine for music, which only demands the power in brief bursts.
Note: you can pretty much get a 2nd AXIS sealed unit and another EP2500 amplifier, and get a 6dB gain, while keeping the stress on the drivers at a minimum, for about the same price as the new amplifier.
-Chris