X.ai announced today that Grok Voice has become the default engine for Vapi's 12 core voices, enhancing the naturalness and emotional range of 2.5 million voice agents on the platform. The integration aims to improve the conversational quality for developers and users alike. The partnership marks a significant step in advancing voice technology for AI-driven applications.
Vapi conducted an independent, blind evaluation comparing Grok Voice against other providers, where Grok took the #1 spot. In a side-by-side poll on X, over 4,500 users were split 50/50 when guessing which voice was the Grok AI clone versus the human original. This result reflects the high level of user engagement and the perceived quality of Grok's voice synthesis.
The announcement comes as Vapi developers can now use Grok to power text-to-speech for their agents through the platform. Additionally, Grok Speech-to-Text and Text-to-Speech are now available in the Vapi Dashboard. New voices and customization options, including custom voice cloning, are also accessible through the Grok Voice API for various use cases such as narration, podcasts, and advertising.
Source: xai
