The Vaulted Harmonies project reconstructs the acoustic and musical heritage of Notre-Dame de Paris through immersive audio-visual experiences spanning multiple centuries of the cathedral's architectural evolution, developed as part of the Past Has Ears at Notre-Dame (PHEND) research project. Building upon the dome screening presented earlier at AVARIG 2026, this presentation focuses on the spatial audio production workflow underpinning the project and the perceptual trade-offs involved in adapting it across dissemination formats. Starting from room impulse responses derived from geometrical acoustic simulations and convolved with anechoic multichannel musical recordings using RoomZ, a dynamic room impulse response panner developed as part of the project, higher-order ambisonic renderings were generated through continuous interpolation along cinematically designed camera trajectories. The 360° dome version, premiered at the Planetarium of the Cité des Sciences et de l'Industrie, decoded these renderings to a 5.1+1 loudspeaker layout. This presentation complements that screening by examining the underlying HOA production chain and presenting selected scenes in third-order ambisonic reproduction, enabling direct perceptual comParison between the two output formats, though in a conventional frontal video projection context. Topics discussed include the design of spatially coherent auralisation trajectories, maintaining a coherent audio-visual narrative across successive historical reconstructions of the cathedral, and the trade-offs related to output format and deployment context, situated within a broader workflow designed to support wide public dissemination of immersive heritage experiences.
