Sound reinforcement is used when the volume in a room or hall needs to be amplified, when the sound intensity drops too much due to the size of the room, when the sound signal is severely impaired due to external influences, noise, loudness, or when the ratio between direct sound and diffuse sound needs to be improved.
The impairments mentioned can cause the signal-to-noise ratio( SNR) to fall below about 10 decibels ( dB) and severely impair intelligibility and dynamics. At such a value, measures should be implemented in the sound reinforcement system to eliminate the impairments.
Sound reinforcement is provided by PA systems and loudspeakers and is intended to improve intelligibility, clarity and distinctness, extend dynamics, ensure the balance of the performance between speech, vocals and musical instruments, and assist in the localization of sound sources. In addition to paying attention to the sound-generating aspects, the design and room layout are the crucial points for sound reinforcement. Here, the room size, the nature of ceilings, walls and floors, the angularity, the seating and the diffusion and absorption surfaces play the decisive role for the sound propagation.
Sound reinforcement is the conceptual implementation of the sound-generating and sound-influencing factors in a sound reinforcement system. The type of loudspeakers, their positioning, the suppression of room resonances, the placement of diffusers and absorbers, and much more, with the aim of achieving undisturbed and intelligible sound propagation.