Experiment of a Multi-channel Spatial Mixing System

In many live performance environments, conventional stereo sound reinforcement effectively collapses into mono due to strong direct sound from the stage. This makes it difficult to form a stable phantom image, especially for vocals, without deploying a dedicated center speaker.

This project explored an alternative multi-channel spatial mixing approach, aiming to achieve intuitive sound image control by physically aligning the “line of hearing” with the “line of sight.” The system was implemented using a 3.1-channel base structure with additional stage rear speakers, relying solely on the audio console’s routing and bus architecture—without an external immersive processor.

Mixing strategies were designed to separate sound image roles: front-heavy sources (vocals, kick, snare, bass) were routed to a center channel, while harmonic and spatial elements were distributed across LR and stage rear speakers. Spatial effects were used to enhance envelopment rather than primary image formation. System tuning treated the rig as two independent systems, focusing on temporal and spectral alignment rather than full electrical unification. While the setup achieved clear physical separation of sound sources, audience feedback revealed an unexpected result: rather than perceiving a cohesive spatial image, listeners experienced instruments as disconnected sound objects.

This outcome highlighted the limitations of purely physical and electrical approaches to spatial mixing, emphasizing the necessity of psychoacoustic and perception-centered design. The project ultimately reframed spatial mixing as a human-perception problem rather than a purely technical routing challenge.