EntangleCodec: A Unified Discrete Audio Tokenizer via Semantic-Acoustic Entanglement

Hui Li, Yangfan Gao, Junlin Shang, Changhao Jiang, Tao Gui, Qi Zhang, Xuanjing Huang


Abstract
Audio tokenizers serve as the discrete interface between continuous audio and Audio Language Models (ALMs), but existing tokenizers often struggle to support both understanding and generation. Reconstruction-oriented codecs preserve acoustic fidelity but lack rich semantics, while semantic-aware tokenizers typically rely on separate semantic and acoustic streams, introducing redundancy or misalignment.

We propose EntangleCodec, a unified discrete audio tokenizer that learns caption-aligned semantic-acoustic representations before quantization. By aligning audio with rich captions rather than ASR transcripts, EntangleCodec captures linguistic content, speaker identity, emotion, prosody, and acoustic scenes within a compact token stream. A flow-matching diffusion decoder further enables high-quality reconstruction across speech, music, and general audio.

EntangleCodec achieves reconstruction quality competitive with specialized codecs, outperforms all codec-based baselines on audio understanding by up to +7.4% on MMAR, and supports both TTS and TTA generation in a unified framework. Furthermore, EntangleCodec-based audio language models demonstrate strong scaling behavior: even at 0.6B parameters, the model surpasses specialized continuous-representation LLMs with over 13B parameters across three benchmarks using 22x fewer parameters; scaling to 8B further establishes new state-of-the-art results on MMAR, highlighting that representation quality is as critical as model scale in audio language modeling. Code and model weights are available at https://anonymous.4open.science/r/EntangleCodec-BA01.
Anthology ID:
2026.findings-emnlp.851
Volume:
Findings of the Association for Computational Linguistics: EMNLP 2026
Month:
October
Year:
2026
Address:
Budapest, Hungary
Editors:
Hung-Yi Lee, Sunipa Dev, Jessy Li, Desmond Elliott
Venue:
Findings
SIG:
SIGDAT
Publisher:
Association for Computational Linguistics
Note:
Pages:
18015–18031
Language:
URL:
https://aclanthology.org/2026.findings-emnlp.851/
DOI:
Bibkey:
Cite (ACL):
Hui Li, Yangfan Gao, Junlin Shang, Changhao Jiang, Tao Gui, Qi Zhang, and Xuanjing Huang. 2026. EntangleCodec: A Unified Discrete Audio Tokenizer via Semantic-Acoustic Entanglement. In Findings of the Association for Computational Linguistics: EMNLP 2026, pages 18015–18031, Budapest, Hungary. Association for Computational Linguistics.
Cite (Informal):
EntangleCodec: A Unified Discrete Audio Tokenizer via Semantic-Acoustic Entanglement (Li et al., Findings 2026)
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PDF:
https://aclanthology.org/2026.findings-emnlp.851.pdf