Posted by Wayne Parham [ 66.137.59.97 ] on May 16, 2004 at 22:44:48:

In Reply to: Playing with Mcbean posted by adavis464 on May 16, 2004 at 11:30:45:

With two sides of the horn parallel, there are notches in response at frequencies determined by the distance between side walls. It may be a non-issue depending on your design, as the frequencies may be outside the passband of the device. For formulas and brief explaination, see the paper below.