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arxiv: 2605.02496 · v1 · submitted 2026-05-04 · 💻 cs.SD · cs.CL

Recognition: unknown

Tibetan-TTS:Low-Resource Tibetan Speech Synthesis with Large Model Adaptation

Chao Wang, Jiaxu He, Jie Li, Jie Lian, Renzeg Duojie, Yongxiang Li, Yuqing Cai

Pith reviewed 2026-05-08 02:52 UTC · model grok-4.3

classification 💻 cs.SD cs.CL
keywords Tibetan TTSlow-resource speech synthesislarge model adaptationtext representation adaptationcross-lingual trainingspeech synthesistokenizer adaptation
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The pith

Adapting a large speech model with Tibetan text handling and cross-lingual training produces stable, natural Tibetan speech from limited data.

A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.

The paper sets out to demonstrate that a large pre-trained speech synthesis model can be turned into a practical Tibetan TTS system even when native audio data is scarce and dialects vary widely. It achieves this through data quality improvements, changes to how Tibetan text is represented and tokenized, and training that borrows from other languages. A sympathetic reader would care because successful low-resource adaptation removes a major barrier for languages whose scripts and pronunciations do not map cleanly, making voice interfaces feasible without first collecting tens of thousands of hours of recordings.

Core claim

The central claim is that a large-model backbone combined with data quality enhancement, Tibetan-oriented text representation and tokenizer adaptation, and cross-lingual adaptive training produces stable, natural, and intelligible Tibetan speech under low-resource conditions, reaching MOS scores of 4.28–4.35 and pronunciation accuracies of 96.6–97.6 percent while outperforming a commercial Tibetan TTS interface.

What carries the argument

The adaptation pipeline of data enhancement, Tibetan-specific text representation and tokenizer changes, plus cross-lingual training applied to a large speech synthesis model backbone.

If this is right

  • The resulting system generates intelligible Tibetan speech with high naturalness scores and beats an existing commercial interface.
  • The same adaptation steps supply a practical route to multi-dialect Tibetan synthesis without separate large datasets for each dialect.
  • Large-model adaptation reduces the amount of native speech data required to reach usable quality for languages with intricate text-pronunciation rules.
  • The approach demonstrates that cross-lingual training can transfer synthesis capability to a new language while preserving stability.

Where Pith is reading between the lines

These are editorial extensions of the paper, not claims the author makes directly.

  • The same pipeline could be tested on other low-resource languages that share complex scripts or dialectal diversity.
  • Adding explicit dialect labels during adaptation might further improve consistency across Tibetan variants.
  • The technique suggests that future unified models could handle multiple under-resourced languages by swapping only the text adapter module.

Load-bearing premise

Data enhancement together with tokenizer adaptation and cross-lingual training is enough to overcome Tibetan dialect variation and the complex written-to-spoken mapping when only limited native recordings are available.

What would settle it

A listening test on previously unseen Tibetan dialects that yields pronunciation accuracy below 90 percent or MOS scores below 3.5 would show the adaptations do not fully solve the stated challenges.

Figures

Figures reproduced from arXiv: 2605.02496 by Chao Wang, Jiaxu He, Jie Li, Jie Lian, Renzeg Duojie, Yongxiang Li, Yuqing Cai.

Figure 1
Figure 1. Figure 1: Unified quality enhancement pipeline for low-resource multi-source Tibetan speech data view at source ↗
Figure 2
Figure 2. Figure 2: Overall architecture of the TTS system 3.3 Tibetan-Oriented Text Representation and Tokenizer Adaptation After data quality enhancement, another key factor affecting model performance under low-resource conditions is how to organize the text input in a way that better matches Tibetan linguistic characteris￾tics. For a speech synthesis system built on the Xingchen large speech model, the input text typicall… view at source ↗
Figure 3
Figure 3. Figure 3: Illustration of Tibetan-oriented text representation and tokenizer adaptation view at source ↗
read the original abstract

Tibetan text-to-speech (TTS) has long been challenged by scarce speech resources, significant dialectal variation, and the complex mapping between written text and spoken pronunciation. To address these issues, this work presents, to the best of our knowledge, the first large-model-based Tibetan TTS system in the industry, built upon a large speech synthesis model developed by Xingchen AGI Lab. The proposed system integrates data quality enhancement, Tibetan-oriented text representation and tokenizer adaptation, and cross-lingual adaptive training for low-resource Tibetan speech synthesis. Experimental results show that the system can generate stable, natural, and intelligible Tibetan speech under low-resource conditions. In subjective evaluation, the MOS scores of the syllable-level and BPE-based systems reach 4.28 and 4.35, while their pronunciation accuracies reach 97.6% and 96.6%, respectively, outperforming an external commercial Tibetan TTS interface. These results demonstrate that combining a large-model backbone with Tibetan-oriented text representation adaptation and cross-lingual adaptive training enables highly usable low-resource Tibetan speech synthesis, and also provides a technical foundation for future unified multi-dialect Tibetan speech synthesis.

Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, simulated authors' rebuttal, and a circularity audit. Tearing a paper down is the easy half of reading it; the pith above is the substance, this is the friction.

Referee Report

2 major / 1 minor

Summary. The paper claims to introduce the first large-model-based Tibetan TTS system by adapting a backbone from Xingchen AGI Lab. It combines data quality enhancement, Tibetan-oriented text representation and tokenizer adaptation, and cross-lingual adaptive training to overcome scarce resources, dialectal variation, and complex text-to-pronunciation mapping. Subjective results report MOS scores of 4.28 (syllable-level) and 4.35 (BPE-based) with pronunciation accuracies of 97.6% and 96.6%, outperforming an external commercial baseline, thereby demonstrating usable low-resource Tibetan speech synthesis and a foundation for multi-dialect systems.

Significance. If the empirical results hold with full methodological transparency, the work would be significant for low-resource TTS research, especially for languages featuring complex orthography and dialectal diversity. Demonstrating effective large-model adaptation with targeted text and cross-lingual steps offers a replicable strategy for other under-resourced languages and supplies concrete metrics supporting practical deployment.

major comments (2)
  1. Abstract: The reported MOS scores and pronunciation accuracies are presented without specifying the number of listeners, test-set size, inter-rater reliability, or statistical comparison to the commercial baseline. These details are load-bearing for the central claim that the three adaptation components produce 'highly usable' output under low-resource conditions.
  2. Experimental results section: The manuscript provides no quantitative information on the hours or utterances of native Tibetan data used for adaptation, the pre-training scale of the backbone model, or ablation results isolating the contribution of tokenizer adaptation versus cross-lingual training. This omission prevents assessment of whether the method genuinely addresses dialect variation and data scarcity.
minor comments (1)
  1. Abstract: The acronym BPE is used without expansion; a parenthetical definition on first use would improve accessibility for readers outside subword-tokenization literature.

Simulated Author's Rebuttal

2 responses · 0 unresolved

We thank the referee for the constructive comments and the recommendation for major revision. We address each major comment below and describe the changes we will make to the manuscript.

read point-by-point responses
  1. Referee: Abstract: The reported MOS scores and pronunciation accuracies are presented without specifying the number of listeners, test-set size, inter-rater reliability, or statistical comparison to the commercial baseline. These details are load-bearing for the central claim that the three adaptation components produce 'highly usable' output under low-resource conditions.

    Authors: We agree that these details are essential to substantiate the claims of usability. The abstract was kept brief, but we will revise it to incorporate the number of listeners, test-set size, inter-rater reliability, and statistical comparison results to the commercial baseline. This will directly support the assertion that the adaptation produces highly usable output. The full evaluation details will also be emphasized in the experimental results section for better transparency. revision: yes

  2. Referee: Experimental results section: The manuscript provides no quantitative information on the hours or utterances of native Tibetan data used for adaptation, the pre-training scale of the backbone model, or ablation results isolating the contribution of tokenizer adaptation versus cross-lingual training. This omission prevents assessment of whether the method genuinely addresses dialect variation and data scarcity.

    Authors: We acknowledge the importance of these quantitative details for assessing the method's effectiveness in low-resource settings and for replicability. In the revised manuscript, we will add specific information on the amount of native Tibetan data (in hours and utterances) used for adaptation, the pre-training scale of the Xingchen AGI Lab backbone model, and ablation experiments that isolate the contributions of the tokenizer adaptation and cross-lingual adaptive training components. These revisions will help demonstrate how the approach addresses dialectal variation and data scarcity. revision: yes

Circularity Check

0 steps flagged

No significant circularity; empirical evaluation only

full rationale

The paper presents an applied TTS system for low-resource Tibetan using a large-model backbone plus data enhancement, tokenizer adaptation, and cross-lingual training. Its central claim is supported solely by reported subjective metrics (MOS 4.28/4.35, pronunciation accuracy 97.6%/96.6%) that outperform an external commercial baseline. No equations, derivations, fitted parameters renamed as predictions, or load-bearing self-citations appear in the abstract or described methods. The work is self-contained against external benchmarks and listener evaluations, with no reduction of any result to its own inputs by construction.

Axiom & Free-Parameter Ledger

0 free parameters · 0 axioms · 0 invented entities

Only abstract available; no explicit free parameters, axioms, or new entities described. Approach uses standard large-model adaptation techniques from existing speech literature.

pith-pipeline@v0.9.0 · 8803 in / 888 out tokens · 65930 ms · 2026-05-08T02:52:41.608215+00:00 · methodology

discussion (0)

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Reference graph

Works this paper leans on

24 extracted references · 15 canonical work pages · 4 internal anchors

  1. [1]

    Tibetan language and ai: A comprehensive survey of resources, methods and challenges,

    C. Huang, N. Tashi, F. Gao, Y . Liu, J. Li, H. Tian, S. Jiang, T. Tsering, B. Ma-bao, R. Duojieet al., “Tibetan language and ai: A comprehensive survey of resources, methods and challenges,”arXiv preprint, 2025, comprehensive survey showing Tibetan is a low-resource language with scarce datasets and limited AI/NLP support. [Online]. Available: https://arx...

  2. [2]

    Tlue: A tibetan language understanding evaluation benchmark,

    F. Gao, C. Huang, N. Tashi, X. Wang, T. Tsering, B. Ma-bao, R. Duojie, G. Luosang, R. Dongrub, D. Tashi, H. W. X. Feng, and Y . Yu, “Tlue: A tibetan language understanding evaluation benchmark,” 2025. [Online]. Available: https://arxiv.org/abs/2503.12051

  3. [3]

    Tibstc-cot: A multi-domain instruction dataset for chain-of-thought reasoning in language models,

    F. Gao, C. Huang, N. Tashi, Y . Liu, X. Wang, T. Tsering, B. Ma-bao, R. Duojie, G. Luosang, R. Dongrub, D. Tashi, X. Feng, H. Wang, and Y . Yu, “Tibstc-cot: A multi-domain instruction dataset for chain-of-thought reasoning in language models,” 2025. [Online]. Available: https://arxiv.org/abs/2508.01977 8

  4. [4]

    Tib-stc: A large-scale structured tibetan benchmark for low-resource language modeling,

    C. Huang, F. Gao, Y . Liu, N. Tashi, X. Wang, T. Tsering, B. Ma-bao, R. Duojie, G. Luosang, R. Dongrub, D. Tashi, X. Feng, H. Wang, and Y . Yu, “Tib-stc: A large-scale structured tibetan benchmark for low-resource language modeling,” 2025. [Online]. Available: https://arxiv.org/abs/2503.18288

  5. [5]

    Natural tts synthesis by conditioning wavenet on mel spectrogram predictions,

    J. Shen, R. Pang, R. J. Weiss, M. Schuster, N. Jaitly, Z. Yang, Z. Chen, Y . Zhang, Y . Wang, R. Skerry-Ryan, R. A. Saurous, Y . Agiomyrgiannakis, and Y . Wu, “Natural tts synthesis by conditioning wavenet on mel spectrogram predictions,” in2018 IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP), 2018, pp. 4779–4783

  6. [6]

    Fastspeech 2: Fast and high- quality end-to-end text to speech,

    Y . Ren, Y . Ruan, X. Tan, T. Qin, S. Zhao, Z. Yan, and S. Xiao, “Fastspeech 2: Fast and high- quality end-to-end text to speech,” inInternational Conference on Learning Representations (ICLR), 2021

  7. [7]

    Lhasa-tibetan speech synthesis using end-to-end model,

    Y . Zhao, P. Hu, X. Xu, L. Wu, and X. Li, “Lhasa-tibetan speech synthesis using end-to-end model,”IEEE Access, vol. 7, pp. 140 305–140 311, 2019

  8. [8]

    Tibetan speech synthesis based on pre-trained mixture alignment fastspeech2,

    Q. Zhou, X. Xu, and Y . Zhao, “Tibetan speech synthesis based on pre-trained mixture alignment fastspeech2,”Applied Sciences, vol. 14, no. 15, p. 6834, 2024. [Online]. Available: https://www.mdpi.com/2076-3417/14/15/6834

  9. [9]

    Research on speech synthesis technology based on tibetan rhythmic features,

    M. Li, P. Tsering, and J. Wang, “Research on speech synthesis technology based on tibetan rhythmic features,” in2023 International Conference on Speech and Language Processing, 2023, (Example venue; please replace with accurate source if you have it). [Online]. Available: https://example.org/placeholder

  10. [10]

    TMD-TTS: A Unified Tibetan Multi-Dialect Text-to-Speech Framework for \"U-Tsang, Amdo and Kham Speech Dataset Generation

    Y . Liu, B. Ma-bao, Z. Zhang, Y . Cai, Y . Yu, R. Duojie, and N. Tashi, “Tmd-tts: Unified tibetan multi-dialect text-to-speech,”arXiv preprint, vol. abs/2509.18060, 2025. [Online]. Available: https://arxiv.org/abs/2509.18060

  11. [11]

    FMSD-TTS: Few-shot Multi-Speaker Multi-Dialect Text-to-Speech Synthesis for \"U-Tsang, Amdo and Kham Speech Dataset Generation

    Y . Liu, Z. Zhang, B. Ma-bao, Y . Cai, Y . Yu, R. Duojie, X. Wang, F. Gao, C. Huang, and N. Tashi, “Fmsd-tts: Few-shot multi-speaker multi-dialect text-to-speech synthesis for ü-tsang, amdo and kham speech dataset generation,” 2025. [Online]. Available: https://arxiv.org/abs/2505.14351

  12. [12]

    CosyVoice 2: Scalable Streaming Speech Synthesis with Large Language Models

    Z. Du, Y . Wang, Q. Chen, X. Shi, X. Lv, T. Zhao, Z. Gao, Y . Yang, C. Gao, H. Wang, F. Yu, H. Liu, Z. Sheng, Y . Gu, C. Deng, W. Wang, S. Zhang, Z. Yan, and J. Zhou, “Cosyvoice 2: Scalable streaming speech synthesis with large language models,” 2024. [Online]. Available: https://arxiv.org/abs/2412.10117

  13. [13]

    Neural codec language models are zero-shot text to speech synthesizers,

    C. Wang, S. Chen, Y . Wu, Z. Zhang, L. Zhou, S. Liu, Z. Chen, Y . Liu, H. Wang, J. Li, L. He, S. Zhao, and F. Wei, “Neural codec language models are zero-shot text to speech synthesizers,”

  14. [14]

    Neural Codec Language Models are Zero-Shot Text to Speech Synthesizers

    [Online]. Available: https://arxiv.org/abs/2301.02111

  15. [15]

    Vibevoice: Expressive podcast generation with next-token diffusion,

    Z. Peng, L. Dong, Y . Zhao, J. Wang, S. Chen, Y . Zhang, P. Li, H. Chen, K. Heet al., “Vibevoice: Expressive podcast generation with next-token diffusion,” inInternational Conference on Learning Representations (ICLR), 2026

  16. [16]

    Hifi-gan: Generative adversarial net- works for efficient and high fidelity speech synthesis

    J. Kong, J. Kim, and J. Bae, “Hifi-gan: Generative adversarial networks for efficient and high fidelity speech synthesis,” 2020. [Online]. Available: https://arxiv.org/abs/2010.05646

  17. [17]

    Waveglow: A flow-based generative network for speech synthesis,

    R. Prenger, R. Valle, and B. Catanzaro, “Waveglow: A flow-based generative network for speech synthesis,”CoRR, vol. abs/1811.00002, 2018. [Online]. Available: http://arxiv.org/abs/1811.00002

  18. [18]

    Yourtts: Towards zero-shot multi-speaker tts and zero-shot voice conversion for everyone,

    E. Casanova, J. Weber, C. Shulby, A. C. Junior, E. Gölge, and M. A. Ponti, “Yourtts: Towards zero-shot multi-speaker tts and zero-shot voice conversion for everyone,” 2023. [Online]. Available: https://arxiv.org/abs/2112.02418

  19. [19]

    Transfer learning framework for low-resource text-to-speech using a large-scale unlabeled speech corpus,

    M. Kim, M. Jeong, B. J. Choi, S. Ahn, J. Y . Lee, and N. S. Kim, “Transfer learning framework for low-resource text-to-speech using a large-scale unlabeled speech corpus,” inInterspeech 2022. ISCA, Sep. 2022, p. 788–792. [Online]. Available: http://dx.doi.org/10.21437/Interspeech.2022-225 9

  20. [20]

    Zeroshotaudiotoaudioemotiontransferwithspeakerdisentanglement

    Z. Ying, C. Li, Y . Dong, Q. Kong, Q. Tian, Y . Huo, and Y . Wang, “A unified front-end framework for english text-to-speech synthesis,” inICASSP 2024 - 2024 IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP). IEEE, 2024. [Online]. Available: http://dx.doi.org/10.1109/ICASSP48485.2024.10447144

  21. [21]

    g2pm: A neural grapheme-to-phoneme conversion package for mandarin chinese based on a new open benchmark dataset,

    K. Park and S. Lee, “g2pm: A neural grapheme-to-phoneme conversion package for mandarin chinese based on a new open benchmark dataset,” 2020. [Online]. Available: https://arxiv.org/abs/2004.03136

  22. [22]

    E2 tts: Embarrassingly easy fully non-autoregressive zero-shot tts,

    M. Research, “E2 tts: Embarrassingly easy fully non-autoregressive zero-shot tts,” inIEEE Spoken Language Technology Workshop (SLT), 2024

  23. [23]

    F5-tts: A fairytaler that fakes fluent and faithful speech with flow matching.arXiv preprint arXiv:2410.06885, 2024

    Y . Chen, Z. Niu, Z. Ma, K. Deng, C. Wang, J. Zhao, K. Yu, and X. Chen, “F5-tts: A fairytaler that fakes fluent and faithful speech with flow matching,” 2025. [Online]. Available: https://arxiv.org/abs/2410.06885

  24. [24]

    Grad-tts: A diffusion proba- bilistic model for text-to-speech,

    V . Popov, I. V ovk, V . Gogoryan, T. Sadekova, and M. Kudinov, “Grad-tts: A diffusion proba- bilistic model for text-to-speech,” inInternational Conference on Machine Learning (ICML), 2021. 10