A porous material is far more efficient at high than low frequency absorption. How to improve sound absorption at lower frequencies using this absorber? A. Increase the thickness B. Decrease the thickness C. Mount with and airspace behind D. Both A and C above

A porous material is far more efficient at high than low frequency absorption. How to
improve sound absorption at lower frequencies using this absorber?
A. Increase the thickness
B. Decrease the thickness
C. Mount with and airspace behind
D. Both A and C above
by

1 Answer

Answer :

D. Both A and C above
by

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