I have an oddly-shaped living room that only supported in-wall and in-ceiling speakers. I didn't want to compromise the most-important speaker by putting it in the ceiling so I am putting it above my TV in the wall. The TV is over our gas fireplace so the wall houses the chimney.
Here's the problem: the wall is not enclosed like a normal wall would be with drywall 4" behind the front wall. There's a large cavity of probably 36" behind it to give the chimney room on all sides. I'm not worried about the heat so much since the real 4" chimney is enclosed with a 6" pipe. The chimney also bends away from the speaker so only the elbow of the chimney is about 18" from it.
Should I build a box for the center? The box would easily be constructed since there's a 2x4 directly above, left, and right of the speaker. I would just need to add a bottom 2x4 and then screw in a piece of plywood for a back. I would probably put a piece of sheet metal on standoffs to block the infrared heat coming from the chimney too.
Think the speaker would sound better with a box in this situation? Aren't they built for a tightly enclosed space like a normal wall would be?