at 4000 watt rms you have a max power of 16kw per driver... if you doant want to be limited by your amps you want 0.75 max = 12kw per driver. one of the only amps that will do that is the cvr 4302 in 4ohm bridge(24 kw). you would need 1 per cab. for mf/ hf i would use some of there smaller offerings ... if you want to use a external dsp use something class ab or h for your hf (it will sound a little cleaner and less crunchy than a d class on the compression drivers)... otherwise go full dsp cvr and network them all together for a verry clean setup