Originally Posted by Etch-A-Sketch
It has always been true, that is why it is called the Inverse Square LAW, not the Inverse Square "rule of thumb" or the Inverse Square "estimation".
The inverse square law applies to point sources radiating in all directions equally. That means 360 degrees on a horizontal plane, 360 on a vertical plane and everything in between. I don't think this describes the behaviour of sound in a cinema.
As for reverberation... How low do you think those wall panels/treatments in a cinema absorb? Certainly not full spectrum. They just tame the highs...
Alistair Johnston - TV & Film Post, Mastering, Sound Design
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