More Wall Construction Effects

I just ran into this and found the graphic (about 20% of the way down) quite interesting. http://www.avsforum.com/avs-vb/showthread.php?s=&threadid=197643&perpage=20&pagenumber=7

Read part of that thread, and now I'm off to the "mad scientist laboratory" to design a non-magnetically levitated, infinitely rigid, low cost sound impervious wall from old truck tires... :?