Chapters are the unit of work
Paste your text with a blank line between chapters or sections. Each block is generated separately and downloaded as a numbered WAV. Two reasons: the free tier caps a single generation at 600 characters, and — more importantly — editing. When a proofreader finds a typo in chapter four, you regenerate chapter four, not the book. The voice state is reused across generations, so the narrator sounds identical from chapter one to chapter forty.