---
title: Step-Audio-TTS-3B
canonical_url: "https://www.modelscope.cn/models/stepfun-ai/Step-Audio-TTS-3B"
md_url: "https://www.modelscope.cn/models/stepfun-ai/Step-Audio-TTS-3B.md"
repository: stepfun-ai/Step-Audio-TTS-3B
last_updated: 2025-04-23
license: apache-2.0
pipeline_tag: text-to-speech
tasks:
  - text-to-speech
model_type:
  - step1
architectures:
  - Step1ForCausalLM
parameters: 3.5B
tensor_type:
  - BF16
library_name:
  - onnx
  - safetensors
  - pytorch
frameworks:
  - pytorch
downloads: 6275
stars: 46
---

# Step-Audio-TTS-3B

> Step-Audio-TTS-3B - stepfun-ai 在 ModelScope 开源的模型。Step-Audio-TTS-3B represents the industry's first Text-to-Speech (TTS) model trained on a large-scale synthetic dataset utilizing the LLM-Chat paradigm. It has achieved SOTA Character Error Rate (CER) results…

stepfun-ai/Step-Audio-TTS-3B 是 ModelScope 魔搭社区上的 3.5B 参数text-to-speech模型，采用 apache-2.0 许可。

- **Repository**: stepfun-ai/Step-Audio-TTS-3B
- **License**: apache-2.0
- **Tasks**: text-to-speech
- **Parameters**: 3.5B
- **Downloads**: 6275
- **Stars**: 46
- **Last updated**: 2025-04-23

Source: https://www.modelscope.cn/models/stepfun-ai/Step-Audio-TTS-3B

---

# Step-Audio-TTS-3B

Step-Audio-TTS-3B represents the industry's first Text-to-Speech (TTS) model trained on a large-scale synthetic dataset utilizing the LLM-Chat paradigm. It has achieved SOTA Character Error Rate (CER) results on the SEED TTS Eval benchmark. The model supports multiple languages, a variety of emotional expressions, and diverse voice style controls. Notably, Step-Audio-TTS-3B is also the first TTS model in the industry capable of generating RAP and Humming, marking a significant advancement in the field of speech synthesis.

This repository provides the model weights for StepAudio-TTS-3B, which is a dual-codebook trained LLM (Large Language Model) for text-to-speech synthesis. Additionally, it includes a vocoder trained using the dual-codebook approach, as well as a specialized vocoder specifically optimized for humming generation. These resources collectively enable high-quality speech synthesis and humming capabilities, leveraging the advanced dual-codebook training methodology.

## Performance comparison of content consistency (CER/WER) between GLM-4-Voice and MinMo.

<table>
    <thead>
        <tr>
            <th rowspan="2">Model</th>
            <th style="text-align:center" colspan="1">test-zh</th>
            <th style="text-align:center" colspan="1">test-en</th>
        </tr>
        <tr>
            <th style="text-align:center">CER (%) &darr;</th>
            <th style="text-align:center">WER (%) &darr;</th>
        </tr>
    </thead>
    <tbody>
        <tr>
            <td>GLM-4-Voice</td>
            <td style="text-align:center">2.19</td>
            <td style="text-align:center">2.91</td>
        </tr>
        <tr>
            <td>MinMo</td>
            <td style="text-align:center">2.48</td>
            <td style="text-align:center">2.90</td>
        </tr>
        <tr>
            <td><strong>Step-Audio</strong></td>
            <td style="text-align:center"><strong>1.53</strong></td>
            <td style="text-align:center"><strong>2.71</strong></td>
        </tr>
    </tbody>
</table>

## Results of TTS Models on SEED Test Sets.
* StepAudio-TTS-3B-Single denotes dual-codebook backbone with single-codebook vocoder*

<table>
    <thead>
        <tr>
            <th rowspan="2">Model</th>
            <th style="text-align:center" colspan="2">test-zh</th>
            <th style="text-align:center" colspan="2">test-en</th>
        </tr>
        <tr>
            <th style="text-align:center">CER (%) &darr;</th>
            <th style="text-align:center">SS &uarr;</th>
            <th style="text-align:center">WER (%) &darr;</th>
            <th style="text-align:center">SS &uarr;</th>
        </tr>
    </thead>
    <tbody>
        <tr>
            <td>FireRedTTS</td>
            <td style="text-align:center">1.51</td>
            <td style="text-align:center">0.630</td>
            <td style="text-align:center">3.82</td>
            <td style="text-align:center">0.460</td>
        </tr>
        <tr>
            <td>MaskGCT</td>
            <td style="text-align:center">2.27</td>
            <td style="text-align:center">0.774</td>
            <td style="text-align:center">2.62</td>
            <td style="text-align:center">0.774</td>
        </tr>
        <tr>
            <td>CosyVoice</td>
            <td style="text-align:center">3.63</td>
            <td style="text-align:center">0.775</td>
            <td style="text-align:center">4.29</td>
            <td style="text-align:center">0.699</td>
        </tr>
        <tr>
            <td>CosyVoice 2</td>
            <td style="text-align:center">1.45</td>
            <td style="text-align:center">0.806</td>
            <td style="text-align:center">2.57</td>
            <td style="text-align:center">0.736</td>
        </tr>
        <tr>
            <td>CosyVoice 2-S</td>
            <td style="text-align:center">1.45</td>
            <td style="text-align:center">0.812</td>
            <td style="text-align:center">2.38</td>
            <td style="text-align:center">0.743</td>
        </tr>
        <tr>
            <td><strong>Step-Audio-TTS-3B-Single</strong></td>
            <td style="text-align:center">1.37</td>
            <td style="text-align:center">0.802</td>
            <td style="text-align:center">2.52</td>
            <td style="text-align:center">0.704</td>
        </tr>
        <tr>
            <td><strong>Step-Audio-TTS-3B</strong></td>
            <td style="text-align:center"><strong>1.31</strong></td>
            <td style="text-align:center">0.733</td>
            <td style="text-align:center"><strong>2.31</strong></td>
            <td style="text-align:center">0.660</td>
        </tr>
        <tr>
            <td><strong>Step-Audio-TTS</strong></td>
            <td style="text-align:center"><strong>1.17</strong></td>
            <td style="text-align:center">0.73</td>
            <td style="text-align:center"><strong>2.0</strong></td>
            <td style="text-align:center">0.660</td>
        </tr>
    </tbody>
</table>

## Performance comparison of Dual-codebook Resynthesis with Cosyvoice.

<table>
    <thead>
        <tr>
            <th style="text-align:center" rowspan="2">Token</th>
            <th style="text-align:center" colspan="2">test-zh</th>
            <th style="text-align:center" colspan="2">test-en</th>
        </tr>
        <tr>
            <th style="text-align:center">CER (%) &darr;</th>
            <th style="text-align:center">SS &uarr;</th>
            <th style="text-align:center">WER (%) &darr;</th>
            <th style="text-align:center">SS &uarr;</th>
        </tr>
    </thead>
    <tbody>
        <tr>
            <td style="text-align:center">Groundtruth</td>
            <td style="text-align:center">0.972</td>
            <td style="text-align:center">-</td>
            <td style="text-align:center">2.156</td>
            <td style="text-align:center">-</td>
        </tr>
        <tr>
            <td style="text-align:center">CosyVoice</td>
            <td style="text-align:center">2.857</td>
            <td style="text-align:center"><strong>0.849</strong></td>
            <td style="text-align:center">4.519</td>
            <td style="text-align:center"><strong>0.807</strong></td>
        </tr>
        <tr>
            <td style="text-align:center">Step-Audio-TTS-3B</td>
            <td style="text-align:center"><strong>2.192</strong></td>
            <td style="text-align:center">0.784</td>
            <td style="text-align:center"><strong>3.585</strong></td>
            <td style="text-align:center">0.742</td>
        </tr>
    </tbody>
</table>

# More information
For more information, please refer to our repository: [Step-Audio](https://github.com/stepfun-ai/Step-Audio).
