SymphonyGen: 3D Hierarchical Orchestral Generation with Controllable Harmony Skeleton

arXiv:2604.25498v1 Announce Type: cross Abstract: Generating symphonic music requires simultaneously managing high-level structural form and dense, multi-track orchestration. Existing symbolic models often struggle with a "complexity-control imbalance", in which scaling bottlenecks limit long-term granular steerability. We present SymphonyGen, a 3D hierarchical framework for contemporary cinematic orchestration. SymphonyGen employs a cascading decoder architecture that decomposes the Bar, Track,