You can bi-amp those 805's but the Rotel puts out 5 x 200 watts per channel, 200 watts is more than enough for those speakers. If you want to a simple Google search will show you diagrams of both horizontal and vertical bi-amping.
Rotel and Bi-Amping
Does any know the answer to this question? I have the Rotel RSP-1576 surround processor and the Rotel RMB-1585 multichannel amp powering a pair of the B&W 805 D3 and the B&W 700 series HTM71 S2 center channel. A simple 3.1 system (I'm saving up for a pair of rears to buy next year to complete a 5.1 system). Anyway, does anyone know if I can bi-amp the 805s with the RSP-1576? I have looked everywhere in the manual and though it mentions bi-amplification it doesn't seem to show you how to set it up. I've emailed Rotel and haven't heard back yet.