The room L and W are fine. Mine is about the same (see system pic).
You can place the speakers 3 ft or more out from the wall behind them. Your listening position will have to be no more than 6 - 8 ft in front of the speakers in order for you to enjoy a proper soundstage in a room only 12 feet wide; that's simply how it works ;--) It's called "nearfield" listening (as in a control room or mixing booth) because you are close enough to the speakers (the NEAR field) that secondary reflections from the walls go behind your listening position and don't affect the holographic image (soundstage). So the only acoustic treatment you will need are not wall panels, but bass traps to eliminate standing waves and reinforcement nodes when or rather IF, they occur at your listening position -- otherwise, who cares ;--)
You do have one room dimension that, depending on the type of speaker you will use, can present a problem, and that is the low ceiling. If you had dipole speakers (panel or ribbon) like mine, the low ceiling wouldn't matter because those types of speakers radiate very little in the up/down direction. But cones and domes radiate omnidirectionally, (equally in all directions) so you WILL get ceiling and floor reflections from the RX6's. Now . . . since you are going to be listening "nearfield" (close to the speakers) the ceiling reflections will come down behind your listening position, so no problem with them -- but floor reflections will be a problem:
The bass reflex port on the RX6 is about 18" from the floor, and a lot of low bass comes out of it. This time, the problem IS that you are sitting so close ;--) and the floor reflections from the sound coming out of the port will be literally "in your face". So you have to kill that reflected energy which will conflict with the clean bass coming directly out of the speaker. There are two-and-a-half ways to achieve this:
1.5 = put the speakers on (approximately) 8 inch high stands (you don't want to get the midranges up too high above your ears ;--) Alternatively, skip the stands, but tilt the speakers back slightly until the excess bass reinforcment goes away.
2 = use some thick, cut-pile wool carpet, at least between the speakers and your listening position, and extending to the sidewalls. For best absorbtion, use WOOL, not synthetic, and DO NOT use a pad under the carpet. Broadloom comes in 12 foot wide rolls, so you can usually find remnants cheeep ;--)
And of course, you can combine both strategies.
Neil
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