A statistical method for calculation of the acoustical parameters of lambertian enclosures (that is, enclosures with diffusely reflecting boundaries) is presented. The theory considers the distribution of sound particles over the boundaries of the enclosures. The method includes the familiar Kuttruff Integral Equation. A homogeneous Markov Chain of first order is obtained through the time discretisation of the equations. Applications of this method are demonstrated for the case of a long enclosure and for the case of a real-shaped room. Decay calculations as well as steady-state sound distributions are obtained. The results show that the method is reliable, flexible, and that computation times are low.
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