Low frequency resonator pipe @ 18.5 Hz, what length and width?

Question

Like the infrasound pipe on church organs, would a whistle, blower or subwoofer be a good sound source so the pipe can amplify the infrasound

What material of pipe also?

Answer 1

http://en.wikipedia.org/wiki/Acoustic_re...

f = nv / (2*(L+0.8d))

18.5 = (1 * 344) / (2 * (L + 0.8d))

make d 0.5 meters to accomodate an 18" (max) subwoofer

L = 8.897 meters

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