Gemini 3.1 Flash TTS × BibiGPT

On 2026-04-15 Google released Gemini 3.1 Flash TTS (Preview): a low-cost, expressive, steerable text-to-speech model. BibiGPT turns your video subtitles or AI summaries into multilingual narration without hiring a voiceover artist.

Preview · 2026-04-15 Flash-tier pricing zh/en/ja/ko ready

Key facts (90-second read)

Gemini 3.1 Flash TTS was released by Google on 2026-04-15 in Preview. It is a low-cost TTS model optimized for expressive, controllable voice. Paired with Gemini Embedding 2 (GA on 2026-04-22) it enables an end-to-end video retrieval + narration pipeline — most of whose building blocks already ship inside BibiGPT.

Features

What is Gemini 3.1 Flash TTS?

Flash TTS is the text-to-speech preview in the Gemini 3.1 family. It keeps Flash-tier latency and cost while boosting expressiveness and controllability.

Flash-tier cost TTS

Positioned against OpenAI gpt-audio and Azure Neural TTS, but priced at Flash tier — batch narration for long-form video becomes economically viable.

Expressive and steerable

Controls for emotion, pauses, emphasis — the watershed feature for AI voiceover. Same script can render in serious / playful / casual tones.

Paired with Embedding 2 GA

Gemini Embedding 2 reached GA on 2026-04-22. Combined with Flash TTS it powers an end-to-end video retrieval → narration pipeline.

Why it matters for BibiGPT users

BibiGPT already produces multilingual scripts and subtitles. Flash TTS is the missing last mile to studio-quality narration.

AI voiceover without a booth

Pipe BibiGPT AI summaries, newsletter drafts, or podcast briefs into Flash TTS for multilingual voiceover. Skip narrator, recording booth, and post-production.

Long-form to short-form

Feed lecture or course videos into BibiGPT for chapter segmentation + highlight summaries, then narrate short clips with Flash TTS. Licensing and original language stop blocking.

Research to podcast

Deep Research Agent drafts a report → BibiGPT outlines the script → Flash TTS narrates. Ship an AI-hosted podcast entirely inside Google + BibiGPT stack.

5 key changes (90-second read)

All sourced from the official Gemini API changelog (2026-04-15).

  1. 1

    Preview available now

    Gemini 3.1 Flash TTS ships as a Preview — any developer with a Gemini API key can call it, no waitlist.

  2. 2

    Flash-tier pricing

    Inherits Flash-family pricing. Large-scale video narration becomes financially feasible compared to studio-tier TTS.

  3. 3

    Controllable expression

    Prompt-level controls for emotion, pacing, pauses, emphasis. The same script can render in multiple tones on demand.

  4. 4

    Paired with Embedding 2 GA

    Gemini Embedding 2 reached GA on 2026-04-22. Combined with Flash TTS it powers a retrieval → narration pipeline for video libraries.

  5. 5

    Works with Deep Research Agent

    The Deep Research Agent update on 2026-04-21 added MCP + File Search. Research first, then use Flash TTS to turn the findings into a podcast or narrated video.

3 typical scenarios for BibiGPT users

Grounded in real BibiGPT user personas; all already actionable today.

General creators — AI voiceover

Pipe BibiGPT AI video summaries, newsletter drafts, or podcast briefs into Flash TTS for multilingual voiceover. Especially efficient for bilingual channels.

BibiGPT users — long to short

Students, teachers and creators feed lecture and course videos into BibiGPT for chapter segmentation + highlight summaries, then use Flash TTS to apply a brand-new narration.

Advanced combo — research to podcast

Deep Research Agent drafts a research report → BibiGPT outlines the script → Flash TTS narrates → ship a polished AI-hosted podcast, entirely inside the Google + BibiGPT stack.

Frequently Asked Questions

Ask us anything!

Turn any video into narration-ready scripts with BibiGPT

BibiGPT summarizes YouTube, Bilibili, and podcasts into multilingual scripts. Plug the output into the Google Gemini Flash TTS API and you get ready-to-ship narration. No custom stack, no learning curve.