When Humans Growl and Birds Speak: High-Fidelity Voice Conversion from Human to Animal and Designed Sounds

Human to non-human voice conversion (H2NH-VC) transforms human speech into animal or designed vocalizations. Unlike prior studies focused on dog-sounds and 16 or 22.05kHz audio transformation, this work addresses a broader range of non-speech sounds, including natural sounds (lion-roars, birdsongs) and designed voice (synthetic growls). To accomodate generation of diverse non-speech sounds and 44.1kHz high-quality audio transformation, we introduce a preprocessing pipeline and an improved CVAE-based H2NH-VC model, both optimized for human and non-human voices. Experimental results showed that the proposed method outperformed baselines in quality, naturalness, and similarity MOS, achieving effective voice conversion across diverse non-human timbres. Demo samples are available atthis https URL

@article{kang2025_2505.24336,
  title={ When Humans Growl and Birds Speak: High-Fidelity Voice Conversion from Human to Animal and Designed Sounds },
  author={ Minsu Kang and Seolhee Lee and Choonghyeon Lee and Namhyun Cho },
  journal={arXiv preprint arXiv:2505.24336},
  year={ 2025 }
}