How does sticking weirdly shaped foam blocks on the walls of a room make noise hard to hear from inside and out?

Question

How does sticking weirdly shaped foam blocks on the walls of a room make noise hard to hear from inside and out?

In: 13

Answer 1

It’s kind of like wavebreakers made from concrete blocks. It breaks up the sound waves, reflecting them back onto themselves.

I also can move slightly, so the sound waves will expend energy moving them. Kind of like how a stone dropping on a mattress will sound less than dropping it on the floor.