Loss in dB per meter
Taking into consideration the effect of the inverse square
law on the propagation of sound waves in free air, how would
you calculate the loss in dB per meter? For example, a sound
source, a one K tone burst produces a level of 90 dB at 3ft.
away from the source. What would be the level in dB at 100yds?
If possible, establish a norm for temperature and relative
humidity. Just a musician trying to design an outdoor sound
The direct answer to your question is that in terms of power,
dB(100 yds) = dB(3 ft)-200, assuming a pure inverse r-squared law.
Jack L. Uretsky
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Update: June 2012