Quote:
Originally Posted by
coctostan 
Would using gradually thicker acoustic foam at the top and bottom of a flat or less curved array work to both delay and attenuate like the CBT model? It could eliminate the crossover complexity and make it easier to construct a small CBT. Something like 2ft tall.
Specifically, I'm thinking about something like what RAAL does with the foam on their ribbons which helps to reduce the beaming inherent to a tall ribbon.
This has been tried before, to attenuate line arrays....I can't remember who wrote the paper, but essentially a tapered attenuating material that was thickest at the ends of the array.....don't think it fared to well, but I can't remember the details...
Problems are getting a material that will attenuate the broadest freq spectrum equally. The thickness must also be adjusted for off-axis response, not easy to do in a multi-way setup, but possible.
JSS