check out the mackie 1400i... it can be bridged and has a built in adjustable and defeatable low pass filter for subwoofer applications. gobs of power.
These amps have proven very reliable at reasonable prices in the pro audio world.
1400 watts @ 4 ohms bridged
1000 watts @ 8 ohms bridged
700 + 700 watts @ 2 ohms stereo
500 + 500 watts @ 4 ohms stereo
300 + 300 watts @ 8 ohms stereo
Ultra-low-noise/ low-distortion design
Fast Recovery circuitry reduces distortion at the edge of clipping and beyond
Two 2nd order, 12dB/octave, Bessel low-cut filters with variable frequency from Off to 170Hz help optimize bass output of your sound system
3rd order, 18dB/octave, Bessel electronic subwoofer crossover with two selectable frequency points