The control of early decay time on auralization results based on geometric acoustic modelling

In the modelling and simulation of acoustic spaces, previous work has focused mostly on optimising the values of reverberation times as the primary acoustic design parameter. According to ISO 3382, Early Decay Time (EDT) is an acoustic parameter which is more relative to perceived reverberance and is actually affected by the very early reflections. In this way EDT becomes an additional and useful method for characterising and optimising a room acoustics simulation. The goal of this project is to investigate the physical changes that affect this acoustic parameter most directly. For this purpose, a model of a 3D shoebox-shape room is used in which the user can control a range of physical acoustic properties relating to the simulation. The influence of the distance between the source-receiver, their distance from the boundaries and the orientation of the source are investigated. For the computer simulation, ODEON 10.1 Auditorium was used which is based on the principle of geometric acoustic techniques. The results are verified through listening tests as well by objective comparison in terms of the resulting effect of each variation.