Introduction to Acoustics - Reverberation Briefly Explanied

Rev-erb-er-a-tion -

Also known as Reverb, Echo, Though echo also refers to Pre-delay which is time between Direct sound sources and the first reflection or "the firse echo".

Shortly after a direct sound, the number of reflections increases to the point were individual reflections become indistinguishable and we are in the last time period: (the reverberation time).

At this point reflections are coming from all directions now and are so frequent that they form together to form a diffuse, gradually decaying reverberation which envelopes the original sound with its warmth and body.

Because sound radiates in all directions, the intensity of the direct sound is relatively small in comparison to the intensity of reverberation.