What to know

  • NotebookLM has added three new audio formats: Brief, Critique, and Debate, in addition to the original Deep Dive.
  • Brief offers quick 1–2 minute summaries; Critique gives expert-style feedback; Debate showcases differing viewpoints via two AI hosts.
  • You access formats via the pencil icon on the Audio Overview card; options include voice, language, and length customization.
  • The rollout includes support in over 80 languages and new AI voices, and applies across platforms including Android, iOS, and desktop.

Since its inception, users have relied on NotebookLM to turn their sources into engaging, AI-driven audio discussions. Now, Google is giving you even more flexibility. Rather than sticking with the same conversational “Deep Dive” format, you can choose one that fits your needs—whether you want speed, feedback, or a discussion of opposing views.

You now have three additional options:

Choose Brief when you want a swift, digestible overview. It runs about one to two minutes—or two to three minutes, depending on the report—and offers a solo-voice summary that hits the core ideas quickly.

Select Critique if you want constructive commentary. It brings in one or two AI hosts to assess your content and suggest improvements—handy for polishing essays, reports, or research sources.

Use Debate when you want to explore different angles. Two AI hosts—each taking a side—discuss your sources in a back-and-forth style, illuminating diverse viewpoints.

These join the original Deep Dive format, where two hosts unpack your material in a conversational dialogue.

How to access new audio overview styles

  • Open your Audio Overview card and tap the pencil icon. This brings up options where you can pick from the four formats.
  • You also control length, language, and—at least in testing—voice options.
  • Once selected, click on Generate.
  • Once generated, these overviews can be downloaded for offline use on Android, iOS, or desktop.

These new formats are rolling out now and are already available to users globally across all supported languages. They follow the recent upgrades that broadened audio and video overviews to over 80 non-English languages. At the same time, NotebookLM introduced new AI voices—male and female—in these formats, though full voice-selection control may vary.