Artificially generated speech is increasingly embedded in everyday life. Voice cloning in particular enables applications where identity preservation is important, such as completing a recording, dubbing in a new language, or preserving the voices of individuals with speech loss. However, in our work, we find that despite the term, voice cloning does not faithfully ''clone'' an individual's voice. Instead, we find that widely-used voice cloning models systematically apply style transfer to source voices. As rated by human annotators, cloned voices are perceived as more authoritative, warm, customer-service-like, and human-like compared to their sources. Human annotators also report greater trust in cloned voices than source voices, and a greater willingness to disclose sensitive personal information to them. Our work furthermore shows that voice cloning leads to homogenization of speaker characteristics, as measured by reduced variance in accent, speaking rate, and the audio embedding space. Together, our results highlight a new set of limitations and risks of voice cloning technology and their potential impact on human behavior.

翻译：人工生成的语音正日益融入日常生活。语音克隆技术尤其能够在需要保留身份特征的应用场景中发挥作用，例如完成录音补录、多语言配音或保留失声者的声音。然而，本研究发现，尽管称为"克隆"，但语音克隆并未忠实地"复制"个体声音。相反，广泛使用的语音克隆模型系统性地对源语音施加了风格迁移。根据人工评估者的评分，相较于源语音，克隆语音被认为更具权威性、温暖感、客服亲和力以及人类拟真度。人工评估者还报告了对克隆语音的信任度高于源语音，并更愿意向其透露敏感个人信息。此外，本研究显示，语音克隆导致说话者特征的均质化——具体表现为口音、语速及音频嵌入空间方差的降低。这些结果共同揭示了语音克隆技术的一系列新型局限与风险，及其对人类行为的潜在影响。