[en] This paper presents an extension of a diffusion model for room acoustics to handle the atmospheric attenuation. This phenomenon is critical at high frequencies and in large rooms to obtain correct acoustic predictions. An additional term is introduced in the diffusion equation as well as in the diffusion constant, in order to take the atmospheric attenuation into account. The modified diffusion model is then compared with the statistical theory and a cone-tracing software. Three typical room-acoustic configurations are investigated: a proportionate room, a long room and a flat room. The modified diffusion model agrees well with the statistical theory (when applicable, as in proportionate rooms) and with the cone-tracing software, both in terms of sound pressure levels and reverberation times.
Disciplines :
Engineering, computing & technology: Multidisciplinary, general & others
Author, co-author :
Billon, Alexis ; Université de Liège - ULiège > Dép. d'électric., électron. et informat. (Inst.Montefiore) > Electroacoustique, acoustique appliquée et éclairage
Picaut, Judicaël
Foy, Cédric
Valeau, Vincent
Sakout, Anas
Language :
English
Title :
Introducing atmospheric attenuation within a diffusion model room-acoustic predictions
Publication date :
2008
Journal title :
Journal of the Acoustical Society of America
ISSN :
0001-4966
eISSN :
1520-8524
Publisher :
American Institute of Physics, Melville, United States - New York
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