I guess that I will have to read the text of Voigt's patent again, but I don't see either the B-is-B or the LCN pipe matching the figures. But, then they could be easily considered correlaries of one or more of the figures.

The terminalogy used today fits neither the physics or the history of pipe design. I guess this is my main point. Voigt pipes, MLTL's, TL's, TQWT's, back horn, corner horn, you get the picture.

I agree with you (agreeing with me?) that the B-is-B is a corner loaded back horn. As such it works completely different from the LCN TQWT. So, I can't consider them the same or correlaries of each other.

Anyway, keep me straight!

Bob