Floorstand speaker sounds "Boomy"

A small square room will have standing waves so there will be locations where the bass reinforces itself and sound boomy, places where the bass will cancel itself. Plus your speakers may contribute by not being flat in the low frequencies. The best room treatment for bass is ASC type tube traps. There are some DIY pages that tell how to make them cheaply.

I would suggest that you raise the speakers off of the floor to decrease the "boom" thast you are hearing.