Cartesia's Sonic-3 is now available on Layercode.

Released last week, Sonic-3 is the fastest and most expressive production-ready TTS model:

• Incredible low-latency: 90ms model latency, 190ms end-to-end makes Sonic-3 ideal for real-time voice AI agents and one of the fastest TTS models available.

• Natural emotion and expressiveness: Sonic-3 handles laughter, excitement, and empathy. You can use SSML tags for emotions, for example: <emotion value="excited" />Oh wow, Valentine's Day snuck up on you, huh? [laughter] Don't worry—we'll get you a table, no problem! Let's make it special.

• Intelligent text handling: Sonic-3 understands text like a human, reading acronyms, homophones, abbreviations, numbers, dates, and addresses correctly based on context.

• Multilingual: Supports 42+ languages with native pronunciation. Full language support coming soon to Layercode.

• Voice cloning: Use Cartesia’s voice cloning features and use custom voices in Layercode.

Sonic-3 + Flux on the edge = the fastest voice AI agents

Sonic-3 is ideal for developers building conversational experiences where responsiveness and human-level expressiveness matter.

We recommend pairing Sonic-3 with Deepgram Flux running on Layercode's edge network to give your Layercode voice agents the benefits of the fastest available STT + TTS combination: ultra-low latency, intelligent turn-taking, and near-human expressiveness delivered reliably to users anywhere in the world.

Try Sonic-3 today

Sonic-3 is available now in your Layercode dashboard. Select it from the TTS model picker under your agent settings.

New to Layercode? Sign up for a developer account and get $100 in credits to test Sonic-3.