The boxes have been altered and reinstalled. I am happy with the result. They now have no insulation behind them and there is a 1/2" air gap between them and the subfloor above. Talk bout cuttin er close, eh? I only ended up using one bag of thin insulation. It went into each box on the bottom face. Same hyper accurate test was performed of knocking on back panel.

I noticed now the peak dropped to around 80hz. This is centered on where these babies will be crossed over. There is also a reduction in lower frequency floor coupling. Good to go! Finally got the program to save pics to memory. smile

Gluing up Reinforced boxes



Resulting noise after alteration.