Cartesia

Cartesia is a voice AI company founded in 2023 in San Francisco by a team from the Stanford AI Lab, focused on low-latency speech synthesis and recognition infrastructure. Its founders introduced the S4 state space model and the Mamba architecture, and its Sonic TTS series has topped the Artificial Analysis speech leaderboard. On AI, the company offers Sonic for text-to-speech, Ink for speech recognition, and Line as a voice agent platform, covering the full real-time conversation stack.