Intel / article

Gemini 3.8 TTS Playground

Source: simonwillison.net
Date: Published Sep 23, 2026

Key takeaways · AI-distilled

Simon Willison built the playground as a bring-your-own-key browser app, which works because the Gemini API has an open CORS policy, letting a page call it directly with the user's key. Compose settings save to bookmarkable URLs for sharing.
Willison highlights that a single API request can define a full conversation between multiple characters, each with a different voice and its own voice style instructions.
In Willison's test, Gemini 3.8 Flash TTS (not the cheaper Flash-Lite) took about 20 seconds to generate 1 minute 18 seconds of two-speaker audio, at a cost of 2.74 cents.

Why it matters

New TTS models with cheap custom voice cloning and multi-character conversation support open up production voice features without needing a dedicated voice-AI vendor.

Read the source simonwillison.net