I have some questions regarding the reflective properties of sound waves... If a spherically propogating wave encounters a plane, the reflection is similar to a light ray, shoots off at the critical angle it approached at, with a new 'image' centre. If the spherical waves encounter another object say a convex object like another sphere (of a smaller radius) what happens? Do they return back along the vector direction from the smaller sphere to the point source? (puzzling to picture i know). What wave parameters would change? Are there set equations governing this behaviour?