Techniques for Multi-Channel Real-Time Spatial Distribution Using Frequency-Domain Processing

The authors have developed several methods for spatially distributing spectral material in real-time using frequency-domain processing. Applying spectral spatialization techniques to more than two channels introduces a few obstacles, particularly with controllers, visualization and the manipulation of large amounts of control data. Various interfaces are presented which address these issues. We also discuss 3D “cube” controllers and visualizations, which go a long way in aiding usability. A range of implementations were realized, each with its own interface, automation, and output characteristics. We also explore a number of novel techniques. For example, a sound’s spectral components can be mapped in space based on its own components’ energy, or the energy of another signal’s components (a kind of spatial cross-synthesis). Finally, we address aesthetic concerns, such as perceptual and sonic coherency, which arise when sounds have been spectrally dissected and scattered across a multichannel spatial field in 64, 128 or more spectral bands.