### Answer I don't have specific information in the available sources about which voice engine powers the Retell platform's built-in voices. The sources mention that Retell AI uses Text-to-Speech (TTS) synthesis to convert AI responses into natural-sounding speech [(1) ]() , and that you can select different voice models in your agent's voice settings [(2) ]() . One Discord thread also references ElevenLabs as a TTS provider option [(3) ]() . For detailed information about which specific voice engines power Retell's platform voices, I'd recommend checking: - [Documentation]() - [Hire certified Retell partner]() Would you like me to try to answer this more generally based on my knowledge instead?

​ To learn more, see the sources I considered: [[1] Speech Processing](https://www.retellai.com/glossary/speech-processing) [[2] My agent is pronouncing em-dashes in responses saying, "A-T" or "O-T" or "OT"](https://community.retellai.com/t/my-agent-is-pronouncing-em-dashes-in-responses-saying-a-t-or-o-t-or-ot/743) [[3] czech language not supported](https://discord.com/channels/1186424376300679209/1464659212394172643) ​

Feel free to tag @AI Evy with additional questions. I also appreciate feedback, it helps me improve.