parbolic dishes (Re: Idea's for recording kit)

["John Hartog" hartogj]

Good 3d point Walt. 

> Generally parabolics are best thought of as producing a small 3d
volume of
> high gain sound at their focus rather than a point of best focus. This
> pretty well covers any small irregularities in the shape of the parabola
>
The size of the focal blob will vary depending on the imperfections of
the dish. Somewhere within this region there will be "points" of best
focus - that is, one or more small areas where the focus is least
diffused.
Though for nature recording, we just move the dish around until we
find the spot that sounds the best and call it good.

John Hartog