Auditorium Acoustic Considerations 5 Flashcards
It plays a very important role in determining its acoustical quality.
Side walls and ceiling potentially useful reflecting surfaces and should be carefully designed to maximize their usefulness.
Rear walls and floors potential sources of useless and harmful reflections which are to be avoided.
Fan shaped plan provides favorable reflection of sound from sides
Shape
The interior surface of the hall should be given utmost attention to make the hall acoustically satisfactory.
If the side walls are parallel, they are to be covered with absorbent
materials.
As the reflections from the near walls are of no use, the rear wall
should be covered with absorbents.
In many large halls, ceiling reflectors, sometimes called clouds is
usually provided, are used to direct sound energy from the stage to
seating area.
The false ceiling positioned near the proscenium should be constructed of reflective material and inclined in a proper way to help reflections of sound from the stage to reach the rear seats in he hall.
Concave shaped ceilings in the form of dome should be avoided.
The rear portion of the ceiling may be treated with sound absorbing
material so that build-up of audience noise is prevented.
The floor should be covered with a carpet. Carpet on the floor not only covers a useless reflecting surface but also greatly reduces audience noise.
Acoustic Treatment of Interior Surfaces
The seats should be arranged in concentric arcs of the circles.
Flat floor seating of more than a few rows is deprived of good visibility and good hearing.
Sloped floor seating is essential for a large audience to have good visibility and good acoustics.
The successive rows of seats must be raised over the preceding ones, with the result that the floor level rises towards the rear end. The rise in level may be about 8 to 12 m3 per row
Seating Arrangements
The hall should be big enough so that sound intensity spreads uniformly over its entire area.
Smaller rooms lead to of sound because of formation of standing waves.
When the length of the hall, is very large in comparison to the
longest wavelength of sound, the room is considered to be large in the acoustical sense and the sound within such a hall may be regarded as spread uniformly.
Volume
