Audience
AI safety researchers and developers evaluating or building speech-based conversational AI.
About Dessa
Dessa is Block's speech-to-speech artificial intelligence model for conversational voice research and applications. It takes audio input and produces audio output directly, without converting speech into text as an intermediate step. Trained from scratch on human conversation rather than text, the model supports full-duplex interaction, listening and speaking at the same time, and runs locally on a MacBook Pro with an M4 Max chip or better. It captures conversational cues such as emotion, sarcasm, laughter, pauses, and turn-taking that can be lost in text-based pipelines. Dessa is intended for AI safety researchers and developers studying voice-model behavior, privacy, and real-time interaction. It is a speech model for research and development, not a general-purpose business application or hosted voice-agent platform.
Other Popular Alternatives & Related Software
GPT-Live-1 mini
GPT-Live-1 mini is one of the two GPT-Live voice models rolling out to ChatGPT users globally, designed to bring more natural, intelligent, and responsive voice interaction to everyday conversations. Built with the same full-duplex approach as GPT-Live, it can listen and speak at the same time instead of waiting for rigid turn-by-turn exchanges. The model continuously processes input while generating output, allowing it to decide many times per second whether to speak, keep listening, pause, interrupt, or invoke a tool. This makes conversations feel faster, smoother, and more natural, with active listening, quick back-and-forth, better timing, and fewer awkward interruptions when the user pauses to think. GPT-Live-1 mini also benefits from the new ChatGPT Voice experience, where users can interrupt with a question, ask ChatGPT to slow down, or tell it to stay quiet and listen.
Learn more about GPT-Live-1 mini
GPT-Live-1
GPT-Live-1 is one of the two new GPT-Live voice models rolling out to ChatGPT users globally, built to make talking with AI feel much more like having a real conversation. It is powered by a full-duplex architecture, so it can listen and speak at the same time instead of waiting for one rigid turn to end before the next begins. During conversations, GPT-Live-1 can show it is paying attention with short acknowledgments, engage in quick back-and-forth, pause when the user needs a moment to think, or stay quiet when asked to listen. It continuously processes input while generating output, allowing the model to decide many times per second whether to speak, keep listening, pause, interrupt, or invoke a tool. GPT-Live-1 also separates natural interaction from deeper work: when a question requires web search, reasoning, or more agentic capabilities, it can delegate the task to a frontier model behind the scenes and bring the result back when it is ready.
Learn more about GPT-Live-1
Higgs Realtime
Higgs Realtime is a production-quality, real-time speech-to-speech model and API built for natural, continuous conversation. It is an end-to-end, instruction-tuned, audio-native model that can understand audio, text, or both and generate high-quality responses, while also functioning as a text LLM when given text alone. Designed for live voice agents, it follows conversations, handles interruptions, adapts when requests change mid-sentence, and carries multi-step workflows through to completion. The model is trained specifically for voice-agent reflexes such as natural turn-taking, conversational cadence, tone adaptation, spoken tool preambles, multi-turn state tracking, and robust instruction following through changing requests. Semantic turn detection helps distinguish a completed turn from a pause, while multilingual and code-switched understanding supports more than 100 languages without per-language setup.
Learn more about Higgs Realtime
Grok Voice Think Fast 2.0
Grok Voice Think Fast 2.0 is xAI’s flagship voice model for building real-time assistants, phone agents, and interactive voice systems that stream audio and text bidirectionally over WebSocket. Developers can configure system instructions, high or no reasoning effort, built-in or custom voices, automatic server-side voice activity detection, silence duration, idle re-engagement, playback speed, and session resumption after temporary disconnects. It accepts PCM, G.711 μ-law, G.711 A-law, and Opus audio through JSON or raw binary frames, with configurable PCM sample rates from telephone quality to 48 kHz. It supports more than 20 languages with native-quality accents, automatic language detection, natural responses in the speaker’s language, and seamless code-switching. Language hints and up to 100 key terms improve transcription of regional speech, names, products, codes, addresses, and specialized terminology, while pronunciation replacements correct spoken output.
Learn more about Grok Voice Think Fast 2.0
Integrations
No integrations listed.
Company Information
Block
Founded: 2009
United States
block.xyz/dessa
Videos and Screen Captures
Dark application screen with a pale circular abstract icon centered above the transcript text, “Human winter is coming for sure but you.”
Other Useful Business Software
Train ML Models With SQL You Already Know
Build and deploy ML models using familiar SQL. Automate data prep with built-in Gemini. Query 1 TB and store 10 GB free monthly.
Product Details
Platforms Supported
Mac
On-Premises
Dessa Frequently Asked Questions
Q: What kinds of users and organization types does Dessa work with?
Dessa works with these users and organization types: Mid Size Business, Small Business, Enterprise, Freelance, Nonprofit, Government, and Startup.
Q: What languages does Dessa support in their product?
Dessa supports these languages: English.
