You're probably right but I'm not going to listen to it at max volume all the time. I listen to rock, alternative, meta, ska, a little emo, you know what I mean. Cradle of Filth, Garbage, No Doubt, Portishead, Chevelle, 30 Seconds to Mars, Slipknot...I have a little taste beyond bass. It's just that bass is the main course and those are the side dishes.
A DSP isn't going to serve any function besides crossover points and slopes with your system. I wouldn't waste your money on one unless you intend to change your speaker setup.
A DSP shines when running active, but that requires individual drivers placed in different locations. You really just need passive crossovers, or an amp with adjustable high and low pass filters.
Hell, you can just get capacitors and inductors and make your own crossover networks for alot less money than a DSP with 12 channels of output capability.
Matt