Calculating Acoustic Radiation from apertures driven by Ribbon Loudspeakers

[thadman]

According to the Huygens-Fresnel principle, the wave emanated by some source can be considered a group of point sources, located on the primary wavefront surface and radiating secondary spherical wavelets

For a calculation of a complex pressure outside of the radiating device, it is necessary to know complex pressure in the exit aperture.

http://www.aes.org/tmpFiles/elib/20091022/12398.pdf

For compression and dynamic cone drivers, they might be approximated as pistons below their fundamental mode. We might assume uniform velocity over the surface of the piston, however we can not make such assumptions with regards to ribbon loudspeakers. Their surface does not move with uniform velocity (maximum at center, 0 at boundaries).

How can we calculate the complex pressure in the exit aperture for a ribbon loudspeaker located in a rectangular duct?

I would be very appreciative if you are able to contribute any knowledge or information (journal articles, texts, etc) regarding this phenomenon.

Thanks,
Thadman

 

[skeptic43]

this link might help.

Scroll 1/2 way down for the ribbon radiation patterns.

Ribbon Wavefront Patterns