This is killing me; not sure if I'm over-complicating or under-complicating it. I’m trying to understand if there is any difference between acoustic scattering and diffusion, and how that differs from attenuation. When particles collide, a small amount of heat is created, since the collision is not perfectly elastic. This is attenuation, and since the collision is necessary for both attenuation and scattering/diffusion, doesn’t this all equate to the same thing? If you put soft fibrous material on a wall, an incoming sound wave will congest the particles against each other as well as the fibers of the material, attenuating the sound. Congestion seems kinda the opposite of scattering, though if scattering describes when particles deflect off of a straight course, wouldn’t congestion increase scattering? Just asking that question makes me feel stupid… Installing diffusers instead will break up the wave and bounce multiple waves in multiple directions, having two effects: attenuation (and/or scattering?) through collision, and the division of the magnitude of the initial wave into multiple less powerful waves (converting a single cohesive force into ambient noise). I’ve also read that scattering and diffusion are analogous, and that one is simply a larger form of the other. But wouldn’t “diffusion” of light in fog, for example, be analogous to sound diffused into a fibrous material (attenuation/scattering)?