:- The defects ,that commonly affect the acoustics of a hall and how to eliminate them to design a good auditorium are described as follows:-

1. Defect = NOISE

Any unwanted sound which can be created inside the hall or can be carried by air from outside into the hall is called noise.

Design = Proper site selection

A site with quite surrounding is proper for a hall or auditorium. The background noise level of the hall should be below 40-50 dB.

2. Defect = Echo

Echo is a sound wave reflected from a parallel hard smooth surface. Excessive echo affects the acoustics of the hall.

Design = A splayed floor plan and the covering of interior surface with suitable absorbent material minimize the defect and distribute the sound energy uniformly throughout the hall.

3. Defect = Echelon Effect

Successive echo of a sound from a set of regularly spaced parallel and smooth surfaces cause Echelon effect which makes the original sound unintelligible.

Design = the steps inside the hall should be covered with absorber like carpets.

4. Defect = Insufficient loudness

Excessive absorption and low reflection of the sound leads to this defect.

Design = in addition to loud speaker large sounding boards are used behind the source of sound. The absorbent materials are adjusted for this purpose, as well.