This brings up an interesting question:

When talking about distances to a wall changing the bass; is it a Mountain and Muhammad sort of thing?

I mean, is it conceivable to make a movable but large and inert baffle to place behind the speaker to simulate the proper distance to a wall?

My speakers are pretty well "locked" in position about 26" from the wall and(horrors)inside of cabinets!! But if I can fool the speakers into thinking they were closer.....