The HK 3470 is actually a modern receiver. I bought one from Crutchfield a year or two ago, just to see what it sounded like. Seemed like a good entry-level system for use with small two-way speakers like the one π and two π speakers. And it does, in fact, sound very, very nice. I am impressed with it, especially for the money.About damping all sides of a two π tower speaker, I'm afraid that you might make the speaker a bit boomy. If you add too much insulation material, it will increase the virtual size of the cabinet. So if you're using R13, I suggest you only line the front, top and one side.