Vapi Offers a Free Week of Cartesia Sonic-3 TTS

Vapi is giving its community free, unrestricted access to Cartesia's newly launched Sonic-3 TTS model through its managed API key from October 28 through November 2. Sonic-3 adds emotion and laughter tags, fine-grained speed and volume controls, and support for 27 new languages. Vapi recommends starting with the Kira and Ariana voices for low-latency, natural-sounding agents.