Perceptual aspects of sound scattering in concert halls
Berlin / Logos-Verl. (2015) [Book, Dissertation / PhD Thesis]
Page(s): IX, 132 S. : Ill., graph. Darst.
This work aims to expand the understanding of sound scattering in architectural spaces and the comprehension of its influence on the auditory perception in concert halls. The notion of scattering coefficient, which numerically represents the physical phenomenon of sound scattering, constitutes the main paradigm for the entire work. In a first part, the scattering coefficient is presented in its meaning and implications, providing both the mathematical formulation and the empirical evaluation. Scattering coefficients of new objects, such as pieces of furniture, have been for the first time determined, hence the foundations for a new scattering coefficient open database is laid. A new solution for avoiding recurrent measurement inaccuracies is presented by means of an improved measurement setup, which consists of a revised scale model reverberation chamber. The benefit of having more accurate acoustic computer simulations by using a wider set of experimental data for scattering coefficient is proved by a case study of classroom acoustics. The implementation of scattering coefficient in different room acoustic computer software is shown and discussed by using a concert hall as a case study. In a second part, the relationship between scattering coefficient and auditory perception is explored. Binaural impulse responses have been determined for three different scenarios, such as two virtual enclosed spaces and one real concert hall, and convolved with music samples to be used in listening tests. Results from listening tests show how changes in scattering coefficient of diffusing surfaces affect the perception of music among the audience in concert halls. A difference limen for scattering coefficient is determined by means of auralized binaural room impulse responses, which have been obtained under different scattering conditions. Results from listening tests are shown and discussed.