# Backend Option 3: faster-qwen-tts

`--backend faster` talks to the OpenAI-compatible server from [faster-qwen3-tts](https://github.com/andimarafioti/faster-qwen3-tts), which uses CUDA graph capture for roughly 5-10x faster inference with the same models. **It requires an NVIDIA GPU**.

The easiest way is to run `python audiobook.py` → **Set up a backend… → faster-qwen3-tts** (or `python -m backends.faster path/to/clone/wavs`): the TUI pip-installs `faster-qwen3-tts[demo]` into its managed venv (`envs/tts`), clones the repo, transcribes the `.wav` files with `whisper`, and writes `voices.json` for you. You can also start the server from the hub's **Server** menu, or let a conversion start it automatically.

If you prefer to install the backend yourself (in your own environment, not the managed venv), the manual steps are below. Either way the hub detects a running server by its port, so a manually-installed backend works once its server is up.

Install into your environment (the same one used for qwen-tts is fine):

```bash
conda activate audiobook
pip install -U qwen-tts
pip install "faster-qwen3-tts[demo]"
```

**This backend always uses voice cloning**. The reference voice and language are configured on the **server**, not through the converter. The server does not transcribe reference audio itself, so do it manually or use the `backends.faster` setup wizard (see below).

The pip package does not include the server script, so clone the repository (the `backends.faster` wizard does this for you into `./faster-qwen3-tts`):

```bash
git clone https://github.com/andimarafioti/faster-qwen3-tts
cd faster-qwen3-tts
```

Create a `voices.json` mapping names to reference configurations (.wav to clone, transcript, language). The TUI setup writes this for you; manually it looks like:

```json
{
    "default": {"ref_audio": "voice1.wav", "ref_text": "Transcript of voice 1.", "language": "English"},
    "obama": {"ref_audio": "voice2.wav", "ref_text": "Transcript of voice 2.", "language": "English"}
}
```

Run the server

```bash
python examples/openai_server.py --voices voices.json --port 8000
```

Then from another terminal, run audiobook.py with `--backend faster`

```bash
python audiobook.py --backend faster [--voice NAME]
```