Design of a sound reinforcement system with acoustic calculations for the assembly hall of educational institutions

Sound reinforcement is also required in assembly halls of schools and other educational institutions. For comfortable perception of the sound signal, it is necessary to carry out an acoustic calculation of the room, with the selection of acoustic materials to optimize the reverberation time, and the selection of loudspeakers. The reverberation time depends on the volume of the room; correction is made by selecting facing materials. Without proper cladding of the walls and ceiling of the room, a high reverberation time can form, which will lead to large reflections of sound signals, and a low reverberation time leads to excessive muting of the room. A heavily damped room impairs the propagation of the sound signal. To optimize the reverberation time, a graph of the value versus volume was created; it is displayed in the recommendation SP 51.13330 “NOISE PROTECTION”.

Acoustic calculation using the EASE (Enhanced Acoustic Simulator for Engineer) software allows the computer model of the assembly hall to change the cladding materials to optimize the reverberation time to the recommended values. Simulators of acoustic systems are added to the three-dimensional model of the hall, on the basis of which calculations of acoustic parameters are generated, for example: sound pressure, sound pressure with a reflected signal, speech intelligibility, time of arrival of the sound signal to the audience, sound loss coefficient and others.

Correction of acoustic parameter calculations depends on the location of the loudspeakers and their orientation towards the audience seats. The number of loudspeakers is also determined only by electroacoustic calculations. Having received an accurate calculation with the definition of acoustic systems, you can proceed to the next stage of designing a sound reinforcement system (SRS), namely the selection of additional audio equipment to amplify and control the sound signal. The choice of amplifiers is based on the parameters of the speaker systems, power impedance and connection type. The audio path consists of several mandatory components, including an audio mixing console, phonogram playback equipment, microphones and audio signal processing devices. The last components are selected based on the tasks that need to be implemented in this room. There is a need to include radio microphones and players of various CD and USB formats in the assembly halls of educational institutions.

The project specifies all technical characteristics of the equipment and a detailed connection diagram. Often the department sets the task of designing a sound reinforcement system, according to which our engineers select sound and projection equipment. Based on the calculation, we determine the mounting points for the speaker systems and the location of additional equipment.