Couple of thoughts. The Hartke Aluminum 410 concept was a pretty radical design idea. Radical design ideas seem to go in one of three directions: They do not catch on at all. They fail. (New Coke) They catch on, popularity swells, and eventually they alter the status quo in their category. (the iPod) They develop a following, become popular for a period of time, but fail to materially alter the status quo, and become a niche product. This happens especially when a competing product comes along and becomes a category 2 (Sony MiniDisc, or perhaps the music of Jesus Jones) I'd say the Hartke aluminum cabinet concept evolved more or less like category 3. I never owned one, but I thought they sounded fine. Someone else (David Eden, namely) happened to come along with a more compelling product.