the reverberation time
Reverberation time TR is an essential measure for characterizing the acoustics of a room. It analyzes how sound propagates and reflects off surfaces such as the walls, ceiling and floor of an enclosed space.
Measured in seconds, the reverberation time is the time required for the sound level to drop by 60 decibels (dB) after the sound source has been suddenly interrupted.
A long reverberation time means that a room's surfaces are rather reflective, usually resulting in uncomfortable acoustics. On the other hand, a room with a shorter reverberation time will be more acoustically comfortable.
The volume of the room, its shape, the type of wall, floor and ceiling surfaces, as well as the furniture and occupants, will also have an impact on reverberation time.
When designing a meeting room, theater or other room where acoustic comfort is important, an architect cannot design a space solely on the basis of the CRB (NRC) noise reduction coefficients of the acoustic materials considered. The room's reverberation time must be analyzed to obtain the desired result.
The illustrations on the right show a workroom where, on the figure above, there is no acoustic treatment. The figure below illustrates the room where acoustic panels have been installed on one of the walls and on the ceiling as sound absorbers to control the reverberation of the room. The acoustic curtain installed between the workstations increases the level of confidentiality between them. These different acoustic treatments ensure a pleasant auditory experience for the workroom's occupants.
Acoustics consultants have computerized tools at their disposal, enabling them to model rooms requiring crucial control of the acoustic environment, such as recording studios, theaters and conference rooms, where the quality of the sound environment is essential.
Understanding and mastering the concept of reverberation time is essential for creating sound environments that meet the specific needs of each application.