My ears give out long before the actives do on that Axel F tune.

I have them crossed to the 500s at 40Hz and have the 800 set in my receiver for double-bass when listening in stereo or simulated surround. The 500s are turned up 75%. The 800 is at 40%. The subs can take it but the HP drivers start to misbehave after my ears give out. That's at 107dBC peaks at 14 feet away.

I'm powering them with a 1500-2. I suppose if anyone wants to crank them higher, they can cross them higher.

House of the Rising Sone
Out in the mid or far field
Dedicated mid-woofers are over-rated