[bpape]

If the back isn't covered much with the wood, you'll likely be OK. But if it covers the whole thing, really doesn't matter much the thickness for the most part it will hurt things.

IMO there are 2 other issues besides doing the wall/ceiling corners (which you should consider).

- The null off the back wall should be addressed with some thick absorbtion behind the mix position back by the bed.

- In a room that long with the mix position at 38%, it's very likely that the monitors you have just don't have enough on their own at the bottom end without being closer to a boundary for some added room gain. Have you tried moving the speakers more toward the front wall and a bit farther apart?

Bryan