Use SUN to listen, NotebookLM to look things up
NotebookLM, which Google now calls Gemini Notebook, is a research notebook. You add sources, ask questions about them, and its Audio Overview turns them into a conversation between AI hosts. If what you want is answers drawn from your own documents, it is the right tool, and it speaks more than 80 languages to SUN's 12.
SUN is built for the other half: the episode itself. You can start with nothing but a question, set how many minutes it runs, pick who reads it, ask it questions while you listen, and turn a subject into a course you finish over a week of commutes.
SUN and NotebookLM side by side
| SUN | NotebookLM | |
|---|---|---|
| Where you start | A sentence, a question, or your files | The sources you add to a notebook |
| Length | The minutes you set | Shorter, Default or Longer |
| Voices | One host or two, from SUN's narrators, or your own voice | Its own AI hosts |
| What you get | Podcasts, audio courses, audiobooks | Audio Overviews: Deep Dive, Brief, Critique, Debate |
| Languages | 12: English (American and British), Spanish, French, German, Italian, Dutch, Portuguese, Ukrainian, Russian, Arabic, Chinese, Hindi | More than 80 |
No sources needed
An Audio Overview summarizes the sources in your notebook, so the notebook comes first and the episode follows what is in it. With SUN the sentence is enough: "how the Federal Reserve sets interest rates, 20 minutes, two hosts" becomes a researched episode. When you have the material, attach it, a paper, slides or your notes, several files at once if you like, and the episode is built around it. PDF to podcast
The length, the hosts and the voice are yours
In the composer you set the duration in minutes, one host or two, and the narrator, in any of 12 languages from American and British English to Arabic and Hindi: AI voices. Or record a minute of audio and hear any episode in your own voice. A voice you add stays private to your account.
More than one episode
Choose Audio Course and a subject comes as connected lessons, each building on the one before, pitched at what you say you already know. Choose Audiobook and SUN narrates your text in chapters: AI audiobook generator. The Scheduler makes a show arrive every morning or every Monday with no prompt to write, and the iOS and Android apps keep your place on every device. SUN also makes fiction stories, micro-dramas, music and meditations, and makes a podcast from a photo as well as from a PDF.
Common questions
Is SUN free?
Your first hour of generation is free. After that, Premium monthly or yearly, or pay as you go, with credits that never expire. Plans and pricing
Can I give SUN my PDFs the way I give them to NotebookLM?
Yes. Attach PDFs, documents, slides, notes or images, and the episode is built on them rather than on the subject in general.
How does SUN sound next to NotebookLM?
Play the episode above: it was made from one sentence. SUN's listenability benchmark puts the two tools' scripts side by side on 100 topics.
Is Gemini Notebook the same as NotebookLM?
Yes. Google renamed NotebookLM to Gemini Notebook in July 2026. It is the same product, Audio Overviews included.
Start from a topic with SUN's AI podcast generator. Comparing other tools: best AI podcast generators, ElevenLabs alternative, Speechify alternative, SUN vs Wondercraft.