Transverse standing wave problems in transmission lines

[Shipwrecked]

With a crossover frequency of 1kHz in a rectangular section xmission line about 35cm across, transverse standing waves would seem to be a likelihood. Hs anyone got any experience with dividing the line lengthwise into a number of small tubes which would be too small to allow standing waves within reach of the woofer/xover drive combination?

[planet10]

Besides its primary functions of box and driver bracing, the holey brace you will see in all my speaker designs also distrupts standing wave perpendicular to its surface. It does this by breaking the width into 3 different distances, and providing a place to put damping to best kill them. In a TL you will also have volume fill of something like polyfulff which also does a job on these standing waves.



dave

[Shipwrecked]

Thanks Tom - looks like a good start.

[john k...]

The waves inside the TL, aside form the axial modes are similar to room modes. In addition there are what Earl Geddes referrs to as HOMs. These are disucssed in any good book on advanced acoustics. Adding braces doesn't actually mitigate the problem. Adding braces, making nonrectangular shapes, etc, alters the standing wave characteristics.