Acoustic diffusion and scattering coefficients for room surfaces

摘要: This project concerns quantifying the diffuseness of sound reflections from surfaces by means a diffusion coefficient. Afthough it is now acknowledged that diffuse are important in determining fields within rooms, no standardised coefficient currently exists. Definition universal coefficient would permit comparison different surfaces and aid the understanding diffusion. It also benefit diffuser designers room acoustic computer modellers. Previously proposed parameters for room surfaces investigated new ones developed. One approach to parameterise uniformity scattered energy measured as polar response; number such have been previously published. These appraised using measured predicted 2D 3D polar responses diverse range sample surfaces. The situations which the parameters succeed fail discussed demonstrated that none is ideal. A response coefficient, superior those previously published, is presented. satisfies many criteria ideal measure is likely be standardised Audio Engineering Society. shown the application all is, however, limited. Two recently alternative approaches evaluating scattering coefficient, involve measuring invariance reflected from a surface its orientation, discussed. One these free field technique and other requires reverberant conditions. Practical analysis shows the reverberation chamber method superior. likely ISO. An empirical reverberation technique investigated, as the possibility efficacy from their effect on sound diffuseness. Both require further research. It concluded provide maAmum benefit, choice coefficient is application dependent.