Jack
I use Behringer Truth B2031 monitors through a Behringer UB802 Mixer; quite satisfactory in the small study that is my musical world.
I have a KN7000 and a PSR3000 connected through this setup. The Yamaha really needs the speakers as it is a bit "thin", but the KN7000 is very good on its internal speakers but excellent through the Truths.
When I'm allowed out into a much larger room the whole rig is awesome.
Keith