New Klipsch client here and first "hi-fi" system in about 30 years. I have a basement room that is 24W x 21.5D x 8H. It is concrete slab floor. My R-28F's are seven feet away and about seven feet apart, right now. I've moved them wider apart, closer, next to the wall, away from the wall and still having a problem with bass. I know they aren't sub replacements. I have an SB16 on the list for future purchase when the wife is away. However, these things are producing some nice bass just not delivering them to me in the right spot.
Sitting down in the listening positioning, there is very little bass. When I stand about half way all the way through to full stand it sounds INCREDIBLE. I can't figure this out. My couch is standard height, even a little higher than most actually. If I move further away it's still the same effect. I've toed the speakers in and out with no change in bass.