Given the complexity of the physical laws governing the phenomena of propagation, absorption and diffraction by obstacles, the study of room acoustics can only be approached using simplified models based on laws analogous to those of geometric optics, wave laws and statistical laws.
When these models fail, we try to explain the observed phenomena by appealing to distributions:
These distributions highlight the limits of validity of statistical laws.
In cases where room geometry becomes too complex and none of the above approaches is satisfactory, it becomes necessary to resort to theories involving energy exchange balances. The resulting laws apply equally well to different parts of the same room, and to ensembles made up of several rooms, whether juxtaposed or not.
But the complete study of a room attributes increasing importance to perceptive effects. To describe a room, we need to introduce a number of criteria that reflect the different components involved in defining room quality.