Home Engineering Building Acoustics
Heavy Multipurpose Hall
In such a facility variable acoustics will be used, and often there will be some significant stage equipment. It is also not uncommon for such halls to have the possibility of relocating the stage (e.g., frontal by the small or the large wall, or central). Variable acoustics are used to try to adapt to the intended use, either through mechanical systems changing the appearance of the walls and ceiling, and even the volume of the hall, or by means of electroacoustic enhancement systems. Quite often, there also are retractable stepped seats.
Variable Acoustics through Mechanical Means
The envelope of the hall will often feature dual-sided panels that can be rotated, with one face absorptive and the other reflective. Quite often, this is associated with a variable height ceiling, with a typical 8 m high ceiling for theatre purposes and 15 m high ceiling for music purposes. More to the point, extra-reflective panels can be brought in close to the musicians in order to introduce some early reflections. Last but not least, should music and theatre be considered, a mobile proscenium wall will be needed. Such a wall typically features an upper part that can be lifted inside the stage tower and the lower parts (on each side of the stage opening) that swivel onto the structural walls so as to be able to choose between a small opening with a proscenium wall (theatre mode, with two distinct volumes for stage and audience, respectively) or a large opening (music mode with stage and audience within the same volume) [2, 3].
Variable Acoustics through Electroacoustic Enhancement Systems
There now are a few electroacoustic enhancement systems available on the market. According to the degree of enhancement needed and the multiplicity of situations to be coped with, their complexity is more or less important. They can manage to turn an initially rather dead hall (e.g., with a RT of 1.5 s) into a lively space with a RT greater than 2.2 s. 
|< Prev||CONTENTS||Next >|