Posted by Wayne Parham on July 26, 2003 at 14:13:21

In Reply to: A COMPLETELY Non-Pi question... posted by wunhuanglo on July 26, 2003 at 08:02:51:

I've never built a speaker to use a non-tapered transmission line for a tuning device. But I can't see any reason that having cross-section area equal to diaphragm area should be a requirement. Check out the paper written by Daniel Russell called "Acoustic High-Pass, Low-Pass, and Band-Stop Filters," which contains some information about acoustic waveguides and transmission lines.