Lots of bass at walls, lack of bass in center of room/listening position

I wonder if diffusers behind my speakers would help? In addition to bass traps. Because I can't pull my speakers out further than a foot off the front wall.

Lets say the diffusers, and traps and everything killed all the reflective problems, you have, what do you have left? 

Only what's coming from the baffle face, even the back side of a dipole would be killed.

So taking what MC said the wave lengths and killing the rest, you can only do a few things. Make a little bass everywhere, very even, very controlled, but everywhere. That's out, can't clutter the floor.

or You could EQ the bass, why? Your killing the reflective excess, so you can increase the actual bass in the seated position. BUT you can't kill all the reflective surfaces, so that's kinds out.

But the bass comes after the mids, and the tweets before the mids, so what do you do? You HAVE to move the speakers. NOT I can only move them this much, there is no other option. If you want to fix the problem..

The bass needs to be closer to you, the mids and highs need to be further away. TIMING.... they (lows mids and highs) need to arrive at your ears, at the same time.

Regards

Your speakers are 4.5 foot apart and your 4.5 feet from the speakers?
That is close to you and close together. WOW!

You are in the wrong place and so are the speakers, it sound like, a bit of humor.  Your in the "cancel zone", if the bass was trapped you would have bass, its the bass bouncing from everywhere to the center (where your at) that's the problem. Cheapest solution move your position.

Correct solution, treat the room as much as you can, place your speakers further from you and wider, get yourself a lot closer to the actual, bass bins, either side of you, or forward of the main speakers, it's a timing issue. Either kill the unused bass or get rid of it, (open the doors on the back wall if you have them). Then you can hear the bass in phase, (correct timing).

Regards