213Chapter 9
Modeling and Auralization
by Dominique J. Chéenne, Ph.D.
9.1 Introduction............................................................................. 215
9.2 Acoustical Modeling...................................................................... 215
9.2.1 Physical Models...................................................................... 215
9.2.1.1 Frequency and Wavelength Considerations in Physical Models.............................. 216
9.2.1.2 Time and Distance Considerations in Physical Models.................................... 217
9.2.1.3 Medium Considerations in Physical Models............................................. 217
9.2.1.4 Source and Receiver Considerations in Physical Models................................... 218
9.2.1.5 Surface Materials and Absorption Considerations in Physical Models........................ 219
9.2.2 Computational Models................................................................. 220
9.2.2.1 Geometrical Models............................................................... 220
9.2.2.2 Wave Equation Models............................................................. 225
9.2.2.2.1 Analytical Model: Full-Wave Methodology................................................ 226
9.2.2.3 Numerical Model: Boundary Element Methodology...................................... 227
9.2.2.4 Statistical Models................................................................. 228
9.2.2.5 Small Room Models............................................................... 228
9.2.3 Empirical Models..................................................................... 229
9.2.3.1 Gypsum Cavity Wall Absorption..................................................... 229
9.2.3.2 Absorption from Trees and Shrubs.................................................... 230
9.2.4 Hybrid Models........................................................................ 230
9.3 Auralization............................................................................. 231
9.3.1 The Basic Auralization Process........................................................... 232
9.3.2 Implementation....................................................................... 232
9.3.2.1 Binaural Reproduction Using Loudspeakers............................................. 232
9.3.2.2 Binaural Reproduction Using Headphones.............................................. 232
9.3.2.3 Multichannel Reproduction Using Loudspeakers......................................... 233
9.3.3 Real-Time Auralization and Virtual Reality................................................. 233
9.4 Conclusion.............................................................................. 235
References................................................................................. 236