Floorstanders on wood floor, help

Here's the setup:
- suspended wood floor, joists accessible from below
- jute carpet pad, very dense
- carpet, very dense/tight pile
- B&W N803's

We want to eliminate bass bloom while preserving attacks and PRAT. Here's what we've tried so far...

Nothing, flat on the carpet...
soft attacks/PRAT plus lots of bass bloom; worst of both worlds

Speakers on sorbothane footers on wood boards...
eliminated bass bloom but killed attacks/PRAT; deadly dullness

Spikes long enough to pierce carpet/pad and reach the floor...
great attacks/PRAT but enormous bass bloom; coupling to a 13 x 17 x 8 bass drum is not the right idea!

Spikes just shorter than the carpet/pad thickness, so not quite touching the wood floor...
great attacks/PRAT but still annoying bass bloom on some recordings; best we've tried so far, but could be better

Any ideas to preserve attacks and PRAT while controlling bass bloom? TIA.