[Danny Richie]

I've learned that the way to do it is to use servo subs for the bottom end. They then use their own amp and control system that will allow you to do virtually anything you want with them.

With low end duty handled with a separate amp then your amp has no current demand and sees an easy load. Then use your amp to drive the uppers using passive filters.

And for an all digital system Rich's system is the only one out there that I can recommend. He did his homework, and it is really good.

[HAL]

Thanks Danny! 

[maty]

And... much better with minimum phase PEQ, emulating passive RLC filters, speakers response and the nature. At least with acoustic and electrified instruments. Without Autotune, of course.

Modern commercial recordings - so badly recorded, with low or very low DR, usually with only synthesized instruments are other world.