Well, dampening the enclosures is working. I am now playing with varying amounts of fiberglass and different densities of foam to control the sound. It seems that the in-walls don't like having much of an enclosure behind them at all. Right now I've got the enclosure space about 60 filled with fiberglass (regular house insulation) and 15% open cell foam (used for upholstry). I need to get more materials to continue testing, but having a variety of materials (different densities) seems to give the best sound. At least it has improved to the point that I am no longer embarassed at having spent so much money. My wife is happy with the appearance, and finally I am getting happy with the sound. I had a dramatic improvement when I moved the sub about two feet. I still get the boost from the floor and wall, but getting it away from the back wall and entertainment center removed the boomieness.