Block unveils Dessa voice AI that sounds eerily human

Block, Jack Dorsey's payments company, has unveiled Dessa, a voice AI model trained entirely on human speech that talks without text and runs locally on a MacBook Pro with an M4 Max chip or better. Trained from scratch on a single Nvidia GB200 NVL72 system, Dessa processes audio directly rather than converting speech to text, letting it handle interruptions, laughter and changes in tone.

Reactions split between amazement — Binance founder CZ floated using it for children's education at GiggleAcademy — and warnings that such natural voices could fuel scams, raised by filmmaker Justine Bateman and journalists. Dessa remains a research preview with no disclosed model size, benchmarks or release date; early access goes first to a small group of AI safety researchers. Block's AI lab reports directly to Dorsey and includes former staff from the Toronto startup Dessa, which Square acquired in 2020.