Papers › The Chamber Ensemble Generator: Limitless High-Quality MIR Data via Generative Modeling

The Chamber Ensemble Generator: Limitless High-Quality MIR Data via Generative Modeling

28 Sep 2022arXiv:2209.14458archive 2025-07-28

Yusong Wu, Josh Gardner, Ethan Manilow, Ian Simon, Curtis Hawthorne, Jesse Engel

Data is the lifeblood of modern machine learning systems, including for those in Music Information Retrieval (MIR). However, MIR has long been mired by small datasets and unreliable labels. In this work, we propose to break this bottleneck using generative modeling. By pipelining a generative model of notes (Coconet trained on Bach Chorales) with a structured synthesis model of chamber ensembles (MIDI-DDSP trained on URMP), we demonstrate a system capable of producing unlimited amounts of realistic chorale music with rich annotations including mixes, stems, MIDI, note-level performance attributes (staccato, vibrato, etc.), and even fine-grained synthesis parameters (pitch, amplitude, etc.). We call this system the Chamber Ensemble Generator (CEG), and use it to generate a large dataset of chorales from four different chamber ensembles (CocoChorales). We demonstrate that data generated using our approach improves state-of-the-art models for music transcription and source separation, and we release both the system and the dataset as an open-source foundation for future work in the MIR community.

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assign_expressive_performance lukewys/chamber-ensemble-generator/midi_augmentation.py official repository unverified MIT (permissive) · d7fa9419744b6cd8 · report
expand_intonation_aug_coefficient lukewys/chamber-ensemble-generator/synth_params_augmentation.py official repository unverified MIT (permissive) · 461bfc4d5af1063e · report
get_f0 lukewys/chamber-ensemble-generator/data_postprocess/postprocess_utils.py official repository unverified MIT (permissive) · 06c586ada97c93a0 · report
get_instrument_by_part lukewys/chamber-ensemble-generator/utils/instrument_utils.py official repository unverified MIT (permissive) · a223123373a00d22 · report
json_load lukewys/chamber-ensemble-generator/utils/file_utils.py official repository unverified MIT (permissive) · 29dd2f76070619d6 · report
note_expression_edit lukewys/chamber-ensemble-generator/expression_augmentation.py official repository unverified MIT (permissive) · 25b8a3f051bc0177 · report
pickle_load lukewys/chamber-ensemble-generator/utils/file_utils.py official repository unverified MIT (permissive) · e8b1c08cfe12d960 · report
split_piece_list lukewys/chamber-ensemble-generator/data_postprocess/postprocess_and_unchunk_cocochorales.py official repository unverified MIT (permissive) · 5c6b55d5270959cb · report
yaml_load lukewys/chamber-ensemble-generator/utils/file_utils.py official repository unverified MIT (permissive) · a40695b615185181 · report

Tasks

Information RetrievalMulti-instrument Music TranscriptionMusic Information RetrievalMusic TranscriptionRetrieval

Datasets

Introduced by this paper, per the archive.

CocoChorales

Results from the paper archive 2025-07-28

TaskDatasetModelMetricValueRank at snapshotLeaderboardReport
Multi-instrument Music Transcription Slakh2100 MT3 w/ MT3 Datasets Multi F1 57.85 #3 of 5 Archive leaderboard report
Multi-instrument Music Transcription Slakh2100 MT3 w/ CocoChorales Multi F1 57.44 #5 of 5 Archive leaderboard report

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