Hello Earlgrey,
Bi-amping is possible but why do you want this?
When your room is not that big you can easily get more fluid by using a KR tube amp.
Look and listen to the link below.
This KR VA 340 is a 25 watt KR 300B amplifier driving the Uni II.
The soundtrack is a CD played by the system and recorded by a set of AKG 300b condenser microphones connected to the camera.
http://www.youtube.com/watch?v=c2tN5FVSeTsThe problem you expect with bi-amping is the match between both amps.
You also can go for a KR VA 320 on top and the pass on the botom.
You can always tune your gain of the LS26 into your system.
Good Luck,
Cor