Because there are no big reflections going back to the microphone, first reflection problems are reduced, and because diffusive materials are irregular in shape, flatter echo is eliminated. Although reverberation won’t be eliminated, scattering and breaking up the reflections tends to result in a smoother reverberation at a lower level.While.

Reflection of sound from surfaces is called reverberation. Reverberation time in a room is defined as the time it takes the SPL to decrease by 60 dB after the source of sound is shut off. A certain amount of reverberation is desirable, because it makes speech sound alive and natural.

In a three-dimensional space, there are discrete echoes at the front of the reverb tail and as the reverb tails out the echo density increases. In a two-dimensional sheet, the echoes are the same density from the start of reverberation to the end. Because the speed of sound is much faster in metal than air, plates have a higher “echo” density.