Sounds like you have a fair amount of cubic feet in that room.
At that price point, B&W Nautilus 801 or Vienna Acoustics Mahlers come to mind. Both produce prodigious bass that usually sounds boomy unless the speakers are driven by the right amps in big rooms. The B&W's are pretty impractical because they require bi-amping with serious solid-state amps, but can produce truly low bass (below 30 Hz.) and move a lot of air. The Mahlers have really potent midbass, are easier to drive and are 90 db. sensitive, but drop below 3 Ohms in the bass and require a top-notch solid-state amp to control the woofers. The Mahlers may be tough to place if you listen on the long wall, as they are rear-ported (the B&W's are bottom-ported).
In view of your amplifiers, these suggestions probably do not help much, but it's going to be tough to find a speaker that moves a lot of air with any finesse at that price point that does not require really potent solid-state amplification or that will work with typical tube amps. If you are patient and flexible with speaker placement, maybe a pair of subs would be a better way to go.
At that price point, B&W Nautilus 801 or Vienna Acoustics Mahlers come to mind. Both produce prodigious bass that usually sounds boomy unless the speakers are driven by the right amps in big rooms. The B&W's are pretty impractical because they require bi-amping with serious solid-state amps, but can produce truly low bass (below 30 Hz.) and move a lot of air. The Mahlers have really potent midbass, are easier to drive and are 90 db. sensitive, but drop below 3 Ohms in the bass and require a top-notch solid-state amp to control the woofers. The Mahlers may be tough to place if you listen on the long wall, as they are rear-ported (the B&W's are bottom-ported).
In view of your amplifiers, these suggestions probably do not help much, but it's going to be tough to find a speaker that moves a lot of air with any finesse at that price point that does not require really potent solid-state amplification or that will work with typical tube amps. If you are patient and flexible with speaker placement, maybe a pair of subs would be a better way to go.