Spatial modal reverberation

Spatial reverberation is a topic of growing interest in the audio industry. Many applications, such as virtual and augmented reality, gaming, and others, rely on the spatialisation of an acoustic field to achieve realistic audio rendering. Many established techniques exist for the purpose. Some, such as ambisonics, rely on a codification of the entire audio field. Others, such as Head-Related Transfer Function (HRTF) techniques, rely on an encoding of the receiver in the audio field. Dynamic rendering of a translating receiver is possible but usually comes at a cost, either through increased computational load (e.g., for HRTFs) or reduced perceptual rendering (e.g., for ambisonics). Here, we explore the possibility of rendering a moving receiver dynamically inside an acoustic space via a modal architecture. First, the poles of the acoustic space are retrieved for a number of source–receiver positions within the space. Then, the modal weights are computed at each location. Since the poles are invariant with location, the modal weights can be interpolated across locations to render dynamic reverberation at no additional cost, and without loss of quality.