Listener envelopment : effects of changing the sidewall material in a model of an existing concert hall

This master thesis examines how the perception of listener envelopment is changed when altering the sidewall material in a computer model of a real concert hall. The research question is based on the lack of information on how the frequency content of the late arriving sound energy affects listener envelopment, but also on the conclusion that envelopment is an affect to large degree of late lateral reflective sounds. A computerized model is used for the purpose to take the research of listener envelopment into a more real acoustical situation than before. Alterations of the late lateral reflections are done by using four side wall materials attaining different sets of absorptions coefficients. A listening test is used for evaluating the change of listener envelopment and 21 listeners conducted the test. Results from earlier research were used to explain the attained results from the ANOVA tests. Sidewall materials which absorbs high frequencies and those that are nonabsorbent creates larger sensations of listener envelopment than materials in which absorbs low, low-mid and mid frequencies in this particular hall.Validerat; 20101217 (root