This repository publishes the verified model artifacts used by the Ascend 310B music workstation in Ascend310/samples/case3. Model files are kept at the repository root so ONNX, PyTorch, OM, JSON, and runtime assets remain easy to inspect together.

The current main branch contains all 31 formally published OM models across Piano-DDSP, MIDI-DDSP, and DDSP-VST. Experimental conversions, rejected precision modes, MIDI test files, rendered WAV files, and private task history are not part of the release.

Model Inventory

Family	OM count	Published files	Purpose
Piano-DDSP	4	`ddsp_piano_*-gru-unrolled-fp32-origin.om`	Causal MIDI-conditioned piano control models
MIDI-DDSP	4	`midi_ddsp_expression_.om`, `midi_ddsp_synthesis_.om`	Static Expression and Synthesis migration/benchmark contracts
DDSP-VST Control	22	`<Instrument>_force_fp16.om`, `<Instrument>_mixed_float16.om`	Stateful real-time timbre control
DDSP-VST Feature	1	`ddsp_vst_feature_mixed_float16.om`	1024-sample pitch and loudness feature extraction

The 11 DDSP-VST timbres are Bassoon, Clarinet, Flute, Melodica, Saxophone, Sitar, Trombone, Trumpet, Tuba, Violin, and Vowels. Each control model accepts state[512], f0_scaled[1], and pw_scaled[1]. The Feature model accepts audio[1024] at 16 kHz and emits scaled and physical pitch/loudness values.

For DDSP-VST Control, mixed_float16 is the preferred precision: it improved all four closed-loop error groups for all 11 timbres while keeping median NPU latency effectively unchanged. Only the mixed-precision Feature OM is published. Its force-FP16 candidate met the latency target but was rejected because its pitch output had a large numerical error.

The four MIDI-DDSP OMs are fixed notes32 and frames64 contracts. They prove conversion and inference compatibility but are not the newer stateful-v2 full song bundle. midi_ddsp_reverb_ir.npz is the required host-side reverb asset; it is not an OM model.

Validation

All OM inference and CANN checks were performed on real Ascend 310B hardware, not on the development computer.

Family	Device validation	Evidence
Piano-DDSP	Four FP32-origin OMs passed 10,000 continuous frames against ONNX references	`validation/model-suite-v1.0.1-gru-unrolled-fp32-origin/full-10000/`
MIDI-DDSP	Four OMs loaded and inferred; all outputs were finite and compared against TensorFlow references	`validation/midi-ddsp-ascend8t/`
DDSP-VST Control	22/22 OMs passed ATC, load/inference, 1,024-step precision, repeatability, and timing checks	`validation/ddsp-vst-ascend8t/summary.md` and `DDSP_VST_VALIDATION.zip`
DDSP-VST Feature	Mixed-precision OM passed 1,000-step precision and latency validation with the Violin control OM	`validation/ddsp-vst-feature-v1.0.0/`

The DDSP-VST Control aggregate result covers 11/11 complete timbres and 22/22 successful OMs. Mixed precision reduced median closed-loop NRMSE by 64.17% for amplitude, 64.25% for effective harmonics, 47.43% for noise, and 46.94% for state. The Feature model recorded a 10.21 ms P95 latency and maximum physical errors of 0.141 Hz for pitch and 5.73e-6 dB for loudness.

Raw DDSP-VST ATC logs and summaries are retained without modification in logs/ddsp_vst/DDSP_VST_ATC_LOGS.zip. Exact device, CANN, tensor contract, source hash, model hash, and validation details are recorded in the validation reports. Archives are used here to keep the Hub tree compact without discarding per-model evidence.

Checksums

SHA256SUMS: original Piano-DDSP source artifacts.
OM_SHA256SUMS.txt: Piano-DDSP OM and adjacent contract hashes.
MIDI_DDSP_OM_SHA256SUMS.txt: MIDI-DDSP OM and reverb asset hashes.
DDSP_VST_OM_SHA256SUMS.txt: all 23 DDSP-VST OM hashes.

Download only the deployable OM release and verify it locally:

bash

hf download zhouxzh/piano-ddsp-ascend310 \
  --include "*.om" "midi_ddsp_reverb_ir.npz" "*SHA256SUMS*" \
  --local-dir artifacts/ascend310b-ddsp

Pin a commit or immutable tag with --revision for production deployment.

Runtime Boundaries

OM files target the validated Ascend 310B contracts and require an existing compatible CANN/PyACL runtime.
Neural models predict control/features. Harmonic synthesis, filtered noise, reverb, MIDI release handling, and audio-device routing remain host-side.
A successful model download does not establish compatibility with another Ascend SoC or CANN release; use the published validation evidence.

Sources and Licenses

Piano-DDSP model artifacts are licensed under CC BY-NC-SA 4.0 and retain the MAESTRO and adapted DDSP-Piano notices. MIDI-DDSP and DDSP-VST artifacts retain their upstream Magenta/Apache-2.0 notices. See LICENSE, LICENSES/, and THIRD_PARTY_NOTICES.md before redistribution or commercial use.

Upstream and implementation sources:

Piano-DDSP: https://github.com/zhouxzh/piano-ddsp-pytorch
MIDI-DDSP: https://github.com/magenta/midi-ddsp
DDSP-VST: https://github.com/magenta/ddsp-vst
Ascend deployment: https://github.com/zhouxzh/Ascend310/tree/master/samples/case3