Reverberation-Time Prediction Method for Room Impulse Responses Simulated with the Image-Source Model

The image-source method has become a ubiquitous tool in many fields of acoustics and signal processing. A technique was recently proposed to predict the energy decay (energy-time curve) in room impulse responses simulated using the image-source model. The present paper demonstrates how this technique can be efficiently used to determine the enclosure´s absorption coefficients in order to achieve a desired reverberation level, even with a non-uniform distribution of the sound absorption in the room. As shown in this work, classical expressions for the prediction of an enclosure´s reverberation time, such as Sabine and Eyring´s formulae, do not provide accurate results when used in conjunction with the image method. The proposed approach hence ensures that the image-source model effectively generates impulse responses with a proper reverberation time, which is of particular importance, for instance, for the purpose of assessing the performance of audio signal processing algorithms operating in reverberant conditions.