I had floor-standers in my 15 x 12 room - 8ft ceiling
- speakers were at one end on the 12ft wall.
- sofa on the 15 ft wall to the right
- open double doorway opposite sofa
- bow window behind the listening position
- book case to the right of the listener in the corner
- Hardwood floor with area rug
Two things thing that made a huge difference
- sound deadening material on top of the bookcase
- 8ft vinyl roller blind in front of the window
Both of these eliminated some very bad reflections
There was a very low frequency standing wave issue that only occurred on two tracks - everything else was fine
I had monitor speakers on stands and then went with the Gershman Acoustics Sonogram floor standing speakers, which did not overpower the room - they are really good at lower listening levels
The speakers are superb in most sized rooms as it turn out - my new room is much bigger 16 x 40 with 7.5 ft ceiling
Unfortunately, sound is a fickle beast - no two speakers sound the same or suffer the same issues.
I would suggest trying a speaker with a front bass port or a port that directs the bass downwards - those should minimizes bass related issues.
My monitor speakers had a rear port, which I eventually directed downwards - a very effective.solution
The Sonograms have a large 2" x 8" port at the very bottom, so their bass performance in the smaller room, while good, still presented a small standing wave issue.
In the new room they sound superb, but the speakers are 8 ft from the wall behind them
BTW - you can get standing wave issues with most speakers - it’s more to do with room acoustics and speaker position than the speakers themselves, but the position/direction of the ports can help alleviate much of the standing wave problem
Hope that helps