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arXiv · 2508.04996

REF-VC: Robust, Expressive and Fast Zero-Shot Voice Conversion with Diffusion Transformers

Abstract

In real-world voice conversion applications, environmental noise in source speech and user demands for expressive output pose critical challenges. Traditional ASR-based methods ensure noise robustness but suppress prosody richness, while SSL-based models improve expressiveness but suffer from timbre leakage and noise sensitivity. This paper proposes REF-VC, a noise-robust expressive voice conversion system. Key innovations include: (1) A random erasing strategy to mitigate the information redundancy inherent in SSL features, enhancing noise robustness and expressiveness; (2) Implicit alignment inspired by E2TTS to suppress non-essential feature reconstruction; (3) Integration of Shortcut Models to accelerate flow matching inference, significantly reducing to 4 steps. Experimental results demonstrate that REF-VC outperforms baselines such as Seed-VC in zero-shot scenarios on the noisy set, while also performing comparably to Seed-VC on the clean set. In addition, REF-VC can be compatible with singing voice conversion within one model.

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Yuepeng Jiang, Ziqian Ning, Shuai Wang, Chengjia Wang, Mengxiao Bi, Pengcheng Zhu, Zhonghua Fu, Lei Xie. 2025-08-08. REF-VC: Robust, Expressive and Fast Zero-Shot Voice Conversion with Diffusion Transformers. https://arxiv.org/abs/2508.04996

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