In our prior works, we introduced a scalable streaming speech synthesis model, CosyVoice 2, which integrates a large language model (LLM) and a chunk-aware flow matching (FM) model, and achieves low-latency bi-streaming speech synthesis and human-parity quality. Despite these advancements, CosyVoice 2 exhibits limitations in language coverage, domain diversity, data volume, text formats, and post-training techniques. In this paper, we present CosyVoice 3, an improved model designed for zero-shot multilingual speech synthesis in the wild, surpassing its predecessor in content consistency, speaker similarity, and prosody naturalness. Key features of CosyVoice 3 include: 1) A novel speech tokenizer to improve prosody naturalness, developed via supervised multi-task training, including automatic speech recognition, speech emotion recognition, language identification, audio event detection, and speaker analysis. 2) A new differentiable reward model for post-training applicable not only to CosyVoice 3 but also to other LLM-based speech synthesis models. 3) Dataset Size Scaling: Training data is expanded from ten thousand hours to one million hours, encompassing 9 languages and 18 Chinese dialects across various domains and text formats. 4) Model Size Scaling: Model parameters are increased from 0.5 billion to 1.5 billion, resulting in enhanced performance on our multilingual benchmark due to the larger model capacity. These advancements contribute significantly to the progress of speech synthesis in the wild. We encourage readers to listen to the demo at https://funaudiollm.github.io/cosyvoice3.
核心贡献 · Key contributions
提出通过监督多任务训练的新型语音分词器,提升韵律自然度。 Proposes a novel speech tokenizer via supervised multi-task training to improve prosody naturalness.
引入可微分奖励优化(DiffRO)用于后训练,适用于基于 LLM 的语音合成。 Introduces Differentiable Reward Optimization (DiffRO) for post-training, applicable to LLM-based TTS.
将训练数据从 1 万小时扩展到 100 万小时,覆盖 9 种语言和 18 种中文方言。 Scales training data from 10k to 1M hours, covering 9 languages and 18 Chinese dialects.
将模型参数从 5 亿扩展到 15 亿,提升多语言基准性能。 Scales model parameters from 0.5B to 1.5B, enhancing performance on multilingual benchmarks.
在多个基准上实现零样本多语言语音合成的最优结果。 Achieves state-of-the-art results on multiple benchmarks for zero-shot multilingual speech synthesis.