Sourcery

AssemblyAI CEO Dylan Fox on 120 Million Voice Conversations a Week

Sourcery

Show Notes

Dylan Fox is the founder and CEO of AssemblyAI, the voice AI infrastructure platform behind AI notetakers, medical scribes, drive through ordering, contact centers and humanoid robots. AssemblyAI went through Y Combinator's first AI batch in 2017 and now serves over 1 million developers with roughly 100 million API calls a day. We get into the volume numbers, why weekly conversations are up over 800% in three years, the three macro trends pulling voice into everything, why coding agents turned small businesses into API customers, how data mixture drives 75% of model quality, the humanoid robot speaker problem, on device models, and the disclosure question the entire voice agent industry is avoiding. "It's very easy to optimize for a public open source benchmark. It's very hard to optimize across all these real world applications." We cover › 120 million weekly conversations and 4x YouTube's daily voice volume › Coding agents expanding the TAM by 100x › Context aware voice models and the McDonald's ordering problem › Why humanoid robots can't disambiguate speakers › Whether voice agents should disclose they are AI

Dylan Fox: https://x.com/YouveGotFox Molly O’Shea: https://x.com/MollySOShea Sourcery: ⁠https://x.com/sourceryy

𝐄𝐏𝐈𝐒𝐎𝐃𝐄 𝐋𝐈𝐍𝐊 YouTube: https://youtu.be/xAF7HkX2DXI

𝐒𝐏𝐎𝐍𝐒𝐎𝐑𝐒 • Brex—The modern finance platform, combining the world’s smartest corporate card with integrated expense management, banking, bill pay, & travel. https://brex.com/sourcery • MongoDB–Millions of developers and more than 65,200+ customers across industries, including ~75% of the Fortune 100, rely on MongoDB for their most important applications. With integrated capabilities for operational data, search, real-time analytics, & AI-powered data retrieval, MongoDB helps organizations everywhere move faster, innovate more efficiently, & simplify complex architectures. https://mongodb.com/ai • AssemblyAI–Millions of developers use AssemblyAI to power their voice ai applications and features. One API gives you access to best-in-class speech-to-text, voice agent, and speech understanding models for both pre-recorded and real-time audio. Granola, ClickUp & HeyGen are scaling with AssemblyAI - get $50 of free credits today at http://AssemblyAI.com/sourcery

𝐓𝐈𝐌𝐄𝐒𝐓𝐀𝐌𝐏𝐒 (00:00) Dylan Fox, Founder & CEO at Assembly AI (01:06) AssemblyAI's voice traffic just beat YouTube by 4x (03:33) $100K in GPU credits that started it all (06:39) Why Voice AI is inflecting right now (10:11) AssemblyAI's infrastructure-first strategy (12:41) Handling 120 million weekly calls (14:49) How AI agents are rewriting Internal Ops at AssemblyAI (17:05) The Sovereign AI problem nobody's solved for voice (18:26) Is the Keyboard and Mouse finally dying? (22:33) The problem Humanoid Robotics hasn't solved yet (25:14) The real problem behind translating languages (29:27) Can AI actually talk to animals? (31:24) The real reason Open-Source benchmarks lie to you (34:20) Building websites in chat rooms as a kid (36:48) On-Device AI models are about to change everything (43:03) The people who shaped Dylan's career

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