Orbitune A2-512 Research-NC
Orbitune Compound Hierarchical GPT continued on the combined Aria-MIDI and GigaMIDI research corpus with bounded vectorized contiguous song-local A2 windows.
This checkpoint is for research and non-commercial use only. It is not a whole-song state-carry TBPTT model.
Artifact
| Field | Value |
|---|---|
| Checkpoint | model.pt |
| Architecture | orbitune-compound-hierarchical-gpt-v1 |
| Parameters | 8,857,250 |
| Final global step | 220,813 |
| Cumulative events seen | 4,096,016,384 |
| SHA-256 | e5bd2080ccf084edaa33c0df9864e4d353b4fe184ed199a2ea89a1cc06324fe0 |
| Bytes | 106,635,500 |
| Strict load | PASS |
Training configuration
- Encoding: A2 bounded vectorized contiguous song-local windows
- Batch size: 64
- Sequence length: 512 events
- Precision: bfloat16
- Dropout: 0.1
- Optimizer: fused AdamW, restored from the parent checkpoint
- Learning rate: 3e-4
- Weight decay: 0.01
- Gradient clipping: 1.0
torch.compile: disabled
The continuation started at global step 109,500 / 448,512,000 cumulative events. Optimizer state and Torch, Python, CUDA, and sampler RNG states were restored and preserved.
Final validation
The final checkpoint was evaluated with the fixed a2-seq512-v1 protocol:
- loss:
-1.5476370453834534 - seed:
10001 - 4 batches of batch size 4
- sequence length: 512
- validation events: 98,304
- window hash:
0d76ff62fc73b22190f14b4377d2bc8e0da48710da398ef09efaac35fcd4da4e
Integrity and lineage
Parent checkpoint SHA-256:
4be09e0869af256f8be62e5e596b72471f15f49a6abbedc613a6a3571fd5bca8
Training source revision:
8489870f81a1591515a98e58554e533fcac9d095
The full completion record is provided in run_evidence.json; machine-readable artifact metadata is in manifest.json.
Loading
Use the Orbitune source at the recorded revision. This is a full training checkpoint, including optimizer and RNG state, rather than a Transformers-format model.
from orbitune.compound_base import CompoundHierarchicalGPT
model, payload = CompoundHierarchicalGPT.load_checkpoint(
"model.pt",
map_location="cpu",
)
model.eval()
License and use restrictions
- Source code: Apache-2.0 in the Orbitune repository.
- Model checkpoint: CC-BY-NC-SA-4.0, research/non-commercial use only.
- Training sources include Aria-MIDI and GigaMIDI; GigaMIDI-derived training is restricted to research use.
- Commercial use is prohibited.
No training corpus files are included in this repository.