What is the most human sounding voice conversation/assistant ai out right now?

As of my last knowledge update in October 2021, several AI voice technologies were notable for their human-like sound quality. Some of the most advanced include:

**Google Assistant**: Google's text-to-speech technology has been consistently refined, producing natural-sounding speech.

**Amazon Polly**: This service offers high-quality voice synthesis and includes various lifelike voices in multiple languages.

**Microsoft Azure Speech**: Known for its Neural Text-to-Speech capabilities, it generates very natural and expressive speech.

**OpenAI’s GPT-3**: While primarily known for text generation, it can be integrated with voice systems to create human-like conversations.

**Descript's Overdub**: This tool allows users to create realistic voiceovers by cloning voices, making it seem more human.

**ElevenLabs**: Known for generating some of the most realistic and expressive voice synthesis available.

Advancements in AI voice synthesis continue to evolve rapidly, so there may be newer technologies available since my last update. For the most accurate and current information, checking recent reviews or benchmarks from credible tech sources would be advisable.