Build Using Free Cartesia Sonic 3 TTS All Week on Vapi

Cartesia has launched Sonic-3, a new text-to-speech (TTS) technology that offers high speed and quality, including features like human-like expressivity, multilingual support across 27 languages, and fine-grained controls for speed and volume adjustments. To promote exploration and usage, a partnership with Vapi allows the community to use Sonic-3 for free from October 28 to November 2 via a managed API key, enabling unrestricted access to its production-grade voices. The technology supports natural expressiveness with emotion and laughter tags, and Vapi provides specific configuration recommendations for optimal performance, such as voice selection between Kira and Ariana for different use cases, emotion and expressivity controls for user interaction enhancement, and multilingual capabilities to cater to specific language needs.