There are a myriad of decisions that need to be made before purchasing seating for an auditorium. Auditorium seating is obviously one of the cornerstones of a good venue. Their aesthetics and comfort level contribute greatly to the overall feel of a venue. Another characteristic of great significance, however, is the acoustic property of the chair.
A poorly constructed chair can wreak havoc on the acoustics of an auditorium space. With acoustic engineers dedicating a significant amount of design time to how walls are constructed or the layout of acoustic panels that are placed on those walls, they sometimes overlook the seats themselves which cover a large portion of the auditorium. Few items in the venue will have as much of an impact on the quality of an auditorium's acoustics as the chairs.
Mitigating the challenges that come with attempting to create an acoustically sound environment means working with a seating solution that will address acoustics in two ways, first is when the seat is occupied and second is when it is not occupied. When the bottom of a chair is folded up it will have entirely different acoustic properties than when someone is sitting in it. Engineers use, for example, wood backings under the chairs with evenly spaced holes to minimize sound wave reverberation. The foam padding employed in the seat is another area of importance to be considered. Most qualified chair manufacturers will list the acoustic properties of their chairs in terms of "absorption coefficients". This number is a great way for engineers to determine how their chair is going to perform once installed. Typically these figures will be attained by performing tests in a certified reverberation room laboratory.
Testing methods employed should be according to ASTM C423-90a and E795-92. The laboratory will test at a series of different frequencies, recording the absorption sabins per unit at each frequency to determine the acoustic properties. It can prove useful to test both an occupied and unoccupied seat. The greater the chair's ability to absorb sound waves, the better it will be for your venue. Chairs that reverberate a great deal of sound end up distorting the sound being produced by the performance or presentation in your venue, decreasing clarity and the quality of your auditorium.
Finding the best auditorium seating for your project isn't just about looks. The acoustic properties of your chair go a long way in determining how successful your project will ultimately be.