On the spatial variation of double-sloped decay in coupled-volume concert halls

In a system of coupled rooms, a double-sloped can be observed in the room containing the source when the coupled room is more reverberant. This decay is formed of a first quick energy decrease due to the first room and a second slower one due to the energy which is fed back from the coupled room. Today, this effect is used to obtain simultaneously clarity and reverberance in concert halls. Parameters to achieve a strong double-sloped decay are now well known. In this preliminary work, the spatial variation of the double decay strength within the concert hall is studied using numerical simulations. Firstly, the indicators quantifying the double decay used in this study are presented. Then, the results of two configurations with the same coupling characteristics but with different coupling area locations are compared. Finally, an empirical model based on the statistical theory is proposed.