So it appears the woofers are powered so a low powered amp would do the trick then. How difficult is it to integrate the bass?
Yes, very simple to do, just a volume knob on the amps. The Hypex amps have pre-programmed settings for DSP from Spatial, nothing there for the user to mess with at all. I've had them cranked up for break-in, which takes considerable time. Once my GIK treatment package arrives, I'll reset everything to "normal", as I'll probably have 100-150 hrs by then (2 more weeks).
I'm planning to experiment a bit with power amps, perhaps post that on another thread, as this one is about Don's amp. IMHO I wouldn't do the fleawatt thing in a room of reasonable size. The DS ~30wpc toob'd is very nice match for my medium size room. The drivers themselves can support huge power, but you'd have to leave the room, maybe the house, if you got carried away. But, you won't hurt them. One thing you definitely want is quiet, lower gain structure amps, as you'll hear it on the AMT @97db. The DS Valhalla is dead quiet, which really surprised me.