# Recipe F — Voice-cloned audiobook chapter

# Recipe F — Voice-cloned audiobook chapter

**Outcome:** A `chapter-XX.mp3` file narrated in a cloned voice from a short
reference audio clip. Loop over chapters to bundle a full audiobook.

**Approx cost:** ~$0.03 per chapter (varies with length).

## Prerequisites

- A 30-60 second reference audio clip hosted at a public URL
  (`REF_AUDIO_URL`).
- Chapter text files at `chapter-01.txt`, `chapter-02.txt`, etc.

## Script

```bash
#!/bin/bash
set -euo pipefail

REF_AUDIO_URL="${REF_AUDIO_URL:?must set REF_AUDIO_URL to a publicly reachable mp3/wav}"

for chapter_file in chapter-*.txt; do
  out="${chapter_file%.txt}.mp3"
  echo "Narrating $chapter_file → $out"

  AUDIO_URL=$(cat "$chapter_file" \
    | visa-cli generate speech --json --yes - \
        --ref-audio-url "$REF_AUDIO_URL" \
    | jq -r '.urls[0] // .filePath')

  curl -sL "$AUDIO_URL" -o "$out"
done

echo "Audiobook chapters ready: $(ls -1 chapter-*.mp3)"
```

## Cost breakdown

| Step | Tool | Approx |
|---|---|---|
| Speech (per ~500-word chapter) | `fal-metavoice` | $0.03 |

## Notes

- `generate speech` clones the voice from `--ref-audio-url`; a clean 30-60s
  sample gives the best fidelity.
- Each chapter is a separate paid call — loop over `chapter-*.txt` to bundle
  a full audiobook.