Datasets:

changelinglab
/

cmul2arctic-l1cls

license: cc-by-nc-4.0
arxiv: 2601.14046
task_categories:
  - audio-classification
language:
  - en
  - ar
  - es
  - hi
  - ko
  - vi
  - zh
tags:
  - speech
  - accent
  - l1-classification
  - native-language-identification
size_categories:
  - 10K<n<100K
configs:
  - config_name: default
    data_files:
      - split: train
        path:
          - cmu/train/*.parquet
          - l2arctic/train/*.parquet
      - split: val
        path:
          - cmu/val/*.parquet
          - l2arctic/val/*.parquet
      - split: test
        path:
          - cmu/test/*.parquet
          - l2arctic/test/*.parquet
dataset_info:
  features:
    - name: audio
      dtype:
        audio:
          sampling_rate: 16000
    - name: corpus
      dtype: string
    - name: l1_label
      dtype: string
    - name: speaker_id
      dtype: string
    - name: utt_id
      dtype: string
  splits:
    - name: train
      num_bytes: 4541009465
      num_examples: 15714
    - name: val
      num_bytes: 2397896973
      num_examples: 7919
    - name: test
      num_bytes: 2110676527
      num_examples: 7762
  download_size: 9049582965
  dataset_size: 9049582965

CMU + L2-ARCTIC Combined Dataset for L1 Classification

This dataset combines CMU Arctic (native English speakers) and L2-ARCTIC (non-native English speakers) for L1 (native language) classification research. It is redistributed for the purpose of academic reproducibility.

Audio is embedded in Parquet files for efficient loading via HuggingFace datasets.

Dataset Description

Subset	Source	Speakers	L1 Labels	License
`cmu/`	CMU Arctic	4 native English speakers	`en`	CMU Arctic license (see CMU Arctic website)
`l2arctic/`	L2-ARCTIC	24 non-native English speakers	`ar`, `es`, `hi`, `ko`, `vi`, `zh`	CC BY-NC 4.0

Splits

Split	CMU	L2-ARCTIC	Total
train	2,264	13,450	15,714
val	1,132	6,787	7,919
test	1,132	6,630	7,762
Total	4,528	26,867	31,395

Schema

Column	Type	Description
`audio`	struct	`{path: string, bytes: binary}` - Audio data with original relative path
`corpus`	string	`cmu` or `l2arctic`
`l1_label`	string	L1 language code (`en`, `ko`, `zh`, `ar`, `hi`, `es`, `vi`)
`speaker_id`	string	Speaker identifier
`utt_id`	string	Utterance identifier

License

⚠️ Important: This dataset contains data from two sources with different licenses.

Folder	Source	License	Commercial Use
`cmu/`	CMU Arctic	CMU Arctic license (see CMU Arctic website)	✅ Allowed
`l2arctic/`	L2-ARCTIC	CC BY-NC 4.0	❌ Non-commercial only

Combined usage requires compliance with CC BY-NC 4.0 (non-commercial use only).

Usage

Load Combined Dataset

from datasets import load_dataset, Audio

# Load one split using the pre-defined split metadata
train_ds = load_dataset("y00njaekim/cmul2arctic-l1cls", split="train")

# Or load all splits at once
ds = load_dataset("y00njaekim/cmul2arctic-l1cls")

# Access a sample
sample = train_ds[0]
print(f"L1: {sample['l1_label']}, Speaker: {sample['speaker_id']}")

# Decode audio bytes
audio_bytes = sample["audio"]["bytes"]
audio_path = sample["audio"]["path"]

Attribution

CMU Arctic

Website: http://www.festvox.org/cmu_arctic/index.html
Technical Report: CMU Arctic Report (PDF)

L2-ARCTIC

As requested by the original authors, please cite the following paper if you use L2-ARCTIC:

@inproceedings{zhao2018l2arctic,
    author={Guanlong {Zhao} and Sinem {Sonsaat} and Alif {Silpachai} and
            Ivana {Lucic} and Evgeny {Chukharev-Hudilainen} and John {Levis} and
            Ricardo {Gutierrez-Osuna}},
    title={L2-ARCTIC: A Non-native English Speech Corpus},
    year=2018,
    booktitle={Proc. Interspeech},
    pages={2783–2787},
    doi={10.21437/Interspeech.2018-1110},
    url={http://dx.doi.org/10.21437/Interspeech.2018-1110}
}

Original Source: https://psi.engr.tamu.edu/l2-arctic-corpus/

You can use this dataset with our benchmarking toolkit at https://github.com/changelinglab/prism

@misc{prism2026,
      title={PRiSM: Benchmarking Phone Realization in Speech Models}, 
      author={Shikhar Bharadwaj and Chin-Jou Li and Yoonjae Kim and Kwanghee Choi and Eunjung Yeo and Ryan Soh-Eun Shim and Hanyu Zhou and Brendon Boldt and Karen Rosero Jacome and Kalvin Chang and Darsh Agrawal and Keer Xu and Chao-Han Huck Yang and Jian Zhu and Shinji Watanabe and David R. Mortensen},
      year={2026},
      eprint={2601.14046},
      archivePrefix={arXiv},
      primaryClass={cs.CL},
      url={https://arxiv.org/abs/2601.14046}, 
}

Acknowledgments

This dataset redistribution is provided for academic reproducibility purposes. All credit for the original data collection belongs to the respective research teams at Carnegie Mellon University and Texas A&M University.