I don't really need to say any more. I've always been passionate about the design. The technique in the box is more of a deterrent. Also the broadband used. In self-construction, one would say "mid-range." In the original, an equalizer is also used to "persuade" the speaker to "translate" the speaker to frequencies above 5kHz and below 70 Hz. Even so, the speaker has received a fan base and, of course, plenty of praise from the press. We don't make a copy, but are inspired by the idea. The first design uses the W4-655.