Audio Definition Model (ADM) metadata is central to contemporary object-based audio production and sits at the core of Dolby Atmos workflows. Yet in open research, rapid prototyping, immersive media development, and playback on irregular loudspeaker arrays, Atmos-derived material remains difficult to inspect, translate, and deploy without relying on proprietary tooling. This creates a persistent gap between the spatial audio formats used in industry and the open systems available to researchers, developers, and immersive venues. This paper presents CULT DSP, an open-source spatial audio toolchain designed to address that gap by separating transcoding, scene exchange, playback, and authoring into distinct but interoperable roles. CULT ingests spatial audio exports, extracts and normalizes scene metadata, and exports it for later use; in the authoring direction, the same module packages LUSID scene data and mono stems back into ADM/BWF output. LUSID provides a stable scene and package structure shared across the stack. Spatial Root is a layout-agnostic playback engine for real-time and offline rendering on custom loudspeaker arrays. Its EngineSession API exposes the runtime as a C++ interface used by the GUI, CLI, and external host applications. Four implementation projects extend the toolchain: Spatial Seed uses CULT and LUSID for procedural authoring from stems; LUSIDstreamer treats LUSID frames as lightweight scene-state packets; immersive-allo-root embeds Spatial Root in an AlloLib audiovisual application; and ue-root prototypes a game-engine-facing host path. Together, they show how Atmos-derived metadata can be reused for playback, authoring, inspection, and immersive media development rather than used only for final delivery.