# Cartesia ships Sonic-3.6, topping Artificial Analysis text-to-speech rankings

Canonical page: https://technooptimist.io/stories/cartesia-ships-sonic-3-6-topping-artificial-analysis-text-to-speech-dbbf267d
Date: 27 Aug 2026
About: [Cartesia](https://technooptimist.io/companies/cartesia.md) · [Sonic](https://technooptimist.io/ai/sonic.md)
Original source: https://cartesia.ai/blog/sonic-3.6

Two months after Sonic-3.5, Cartesia rebuilt data, architecture, training and evaluation for Sonic-3.6. It replies in under 90 ms, speaks nearly twice as fast as before, covers 61 locales and ranks first on both Artificial Analysis voice leaderboards.

## Key facts

- Elo 1120 on the controlled-voice board, ahead of Sonic-3.5 (1095) and Eleven v3 (1066).
- Native US-English listeners preferred it over Eleven v3 in 92% of blind tests (company test).
- Adds Odia and Urdu and mixes Hindi and English in one sentence.
- About 132 characters per second, up from 68.

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