Gaussian distribution-based randomised image method

Sweeping echo is an acoustical phenomenon present in perfectly rectangular rooms that is characterised by a continuous increase in pitch arising from the concurrent arrival of multiple higher-order reflections. Even though the room acoustic simulation software predicts their presence, in most rectangular rooms sweeping echoes can hardly be perceived due to the existence of small irregularities in the room geometry. In this paper, the image sources' position randomisation model developed within the randomised image method framework with which the incongruence between the original image method results and in situ measurements can successfully be reduced is replaced with a Gaussian distribution model. The results indicate that with the proposed model an improvement in the stability of the room transfer function across realisations can be achieved.