It might not be the speaker, nor even the rooms acoustics messing with the bass. I have the typical sprung wood floor, which is to say that it is a house with a basement. I built a homemade copy of the Bright-Star sand boxes to absorb the bass resonances - it worked.
This innovation was so efficient at aborbing energy that it sucked some life and trebble out of the speaker too.
To regain the top end but still control the mid-range and bass I placed steel plates under the speakers. I tuned the sound by experimenting to see if it sounded best with one or two speaker feet/spikes resting on the steel - verses the compress wood top.
Final tuning involved purchasing large ceramic concrete cutting disks for the back cones to rest on.
In general I've found the sound of a material when used under audio equipment (including speakers) to mimic the material itself. That is to say, steel sounds strong but cold, glass is clear but can cause glare, wood is natural and warm but can be grainy or soft/soggy.
Look at the members systems, you will see several aftermarket platforms under the hybrid speakers for a good reason (including the foam and rubber ones).
Note: When you raise the speakers you will have to tilt them towards the listening position - they were not designed to sit so high (3-4 inches higher).