Erik, ASC IS expensive. I got lucky and found my Traps for $10 each, including two 16" ! I found them in the mid-90's, listed in The Recycler, a Buy/Sell newspaper in SoCal. I went to the sellers house to pick them up, and the place was empty except for them. Weird! I think he had bought the house to flip, and the Traps were left behind. Bass traps can be made DIY for not much $, for those who aren't as lucky as I.
GIK has a great product line, especially for absorption at first reflection locations, and for diffusion. Bass Traps, though, require more Herculian effort, and ASC pretty much owns that segment of the market.