Re: Calculating change of loudness for increasing distance from the source

Adrian Tuddenham <poppy.uk@xxxxxxxxxxxxxxxxxxxxxxxx> wrote:

...and the inverse square law only applies where the source is small
compared with the distance (when the wavefront is spherical).

This is true for a typical PA application, where you may have a couple
horns separated by 10 feet, but you are concerned with sound levels
a hundred feet away.

However, the fact that you are on the ground and not in free space
makes an appreciable difference.

Generalizing this to a line array is left as an exercise to the folks
at Community. The math is all different, though, because you can no
longer consider it as a point source. But they will send you all kinds
of white papers about it if you ask.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."
.

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