Question

What is reverberation? And how can it be reduced in an auditorium?

Answer 1

Hint: We will first define reverberation and then we will state what causes reverberation and how we can reduce it. We will try to explain it by taking day to day life examples so that we can relate more with what is reverberation.

Complete answer:
Reverberation is basically reflection of sound waves, multiple reflection of sound waves which causes it to produce a lasting effect. Or we can say, persistence of sound after suffering multiple reflections is called reverberation.
Reverberation is almost the same as an echo but the basic difference is the distance between the source of sound and the obstacle which causes reflection. In case of reverberation, the distance between the source of sound and the obstacle which causes reflection is less.
Now we take examples from day to day life in order to understand it better.
In day to day life we experience reverberation, recall when you are sitting in a hall you must have witnessed the persistence and repentance of sound. It is reverberation which is caused by reflection from the walls and ceilings.
Now we know reverberation is caused by reflection of sound by surfaces and in an auditorium sound waves get reflected from walls and ceilings and hence produces repeating sound which can be frustrating during events as repeating of sound is unwanted. But there are ways by which we can minimise the reverberation.
As we know reflected sound causes reverberation so we can use sound absorbents in order to get sound absorbed and hence minimum sound is reflected. We can use different materials for this purpose such as plastics, heavy curtains, fiberglass, porous materials like mineral wool and many more.

Additional information:
Reverberation is quantified on the basis of its time which is called reverberation time. Reverberation time is defined as the time it takes to the sound pressure level (SPL) to decrease by 60 decibels. Simply it is the time required by the sound wave to fade away.

Note:
Reverberation is not always unwanted; it has advantages and disadvantages both.
Reverberation is needed sometimes in musical halls for which sound engineers are hired to construct such roofs that can reflect sound efficiently.