Posted by: "no_mas_films"
> Paul, thank you very much for posting this file! Although the book is
> long out of print, I think his conclusions are valid and will hold
> sway in my choice of microphones for the parabolic I am currently
> building. So far, I have purchased a used AT4041 from eBay and this
> passage reinforces it's use. Thanks again, and could you scan and
> post the rest of this book? :-) Chris
Parabolas back then tended to have longer focal lengths relative to dish
depth. This placed the mic out in the interference pattern in front of
the dish as described. A cardioid would not fully compensate for this.
Also, placed out that far it's wide pickup would include sound direct
from the side that was not part of the reflected sound. The real answer
was to go to dishes that were deeper relative to the focal length, thus
placing the mic within the dish. This is a better and more direct method
of compensating for the interference patterns. And more or less removes
this "advantage" of a cardioid. Most modern parabolic dishes are deeper.
To my mind the even better way to go is to set up the parabola as stereo.
Walt
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