If you are building the room from scratch, and you absolutely must hide the speakers, then consider the suggestions for an acoustically transparent screen which would allow you to build a false wall and hide the speakers behind it. This would at least allow you to plan some breathing room for your speakers, rather than dramatically changing the sound by enclosing speakers that were not designed to be enclosed. That or purchase speakers designed for wall enclosures.
My apologies if it sounds like I am trying to make a big deal out of this but it just so happens that during my recent vacation that I was in a friends house where he ignored my advice and built custom cabinets surrounded with pink insulation stuffed in beside each speaker in his HT room. There may have been other things at play, but I can tell you that I have never heard Paradigms (a speaker I am pretty familiar with) sound so terrible. The difference was not a subtle thing that only an audiophile would notice or think important. He actually brought me in because he was about to bring the speakers back to the store as they sounded aweful to him as well and I was summoned because they were on a short list (including Axioms at the top) that I recommended for him.
The best way that I could describe it in my limited terminology was that he had effective surround sound in the sides and rears (effective directionally)but up front it sounded a bit like he was using speakers that you commonly find built into a TV set.
We didn't have any speaker cable to try them pulled out of the cabinets but we did rig up a coax extension to remove the sub which solved his vibrating drywall problems. I told him he could consider removing the drywall and properly reinforcing the area and placing an isolating material between the drywall and the studs but when he took it out of the wall, he actually admitted it probably should never go back in there as it sounded so much better.
Since I left, he has called to tell me that he temporarily wired the front and center speakers up outside the enclosures and they now sound like what he remembered them to be, a beautiful sounding speaker. Now he is flip flopping between returning the Paradigms for wall units or writing off that his custom cabinetry job was a waste.
Sorry if I sound like I'm ranting but I just don't want someone else to waste money if they won't be happy after. However, as JohnK pointed out. Happiness is relative. Do what will put the biggest smile on your face.
Edit: I was saving this story for when I had time to start it's own thread but it seems better placed here. Also, as a curiosity, I called the local AV shop that I do recommend to people as they have a very experienced owner who knows his stuff and politely asked if they recalled him discussing him putting the speakers in cabinets. He did recall the purchase and also recalls explaining to him why that would not be recommended and showed him some completely invisible, hidden in walls. They are designed to actually blend into the drywall and be painted over. I had heard these before in there and was very pleasantly surprised (despite my doubts) as to how good they sounded at the time. The price, including insulation is CRAZY expensive though. I admit, I prefer to see my speakers for some reason anyways.
Last edited by Murph; 08/25/10 12:09 PM. Reason: POST WASN'T RIDICULOUSLY LONG ENOUGH ALREADY.