Google’s NotebookLM Introduces AI Podcast Tone Customization

Google’s AI note-taking and research assistant NotebookLM now allows users to tailor the tone of their Audio Overviews, which are podcasts featuring AI virtual hosts that summarize and discuss documents shared with NotebookLM, such as course readings or legal briefs.

When creating an Audio Overview, users can select whether they prefer their AI podcasts to be formatted as a “Deep Dive,” “Brief,” “Critique,” or “Debate.”

A Deep Dive features engaging dialogues where two AI hosts explore the topic in depth, asking questions along the way. A Brief provides a concise overview designed to help you quickly understand the essential ideas from your sources.

A Critique offers a review of your sources along with constructive feedback to enhance them, while a Debate entails two AI hosts presenting contrasting views on your sources.

NotebookLM Image Credits: Google

Each of these formats allows you to customize the duration of the AI podcast, whether you want it to be short or long.

In addition to customizable tones, Google is also introducing a highly requested feature to NotebookLM: new voices for the AI podcasts.

This launch comes as Google has been enhancing NotebookLM over the past few months. Recently, the tech giant introduced Video Overviews, enabling users to transform dense multimedia, such as raw notes, PDFs, and images, into easily digestible visual presentations.

Techcrunch event
San Francisco
October 27-29, 2025

NotebookLM has also gained access to a collection of featured notebooks from various authors, publications, researchers, and nonprofits, allowing users to explore a diverse range of topics. Moreover, in May, Google officially rolled out standalone NotebookLM apps for Android and iOS.

The new formats for NotebookLM are rolling out in all languages and are expected to be available to all users this week, according to Google.