Two weeks ago, we opened up Phonon, our small text-to-speech model that runs on your own device. It needs no server and no network, and what you type stays with you.

We've been very happy with the reception so far. So here's the story of the launch: why we built Phonon, what it can do, the demos that came with it, and how it did on Hugging Face's Open TTS Leaderboard.

Most voice AI lives in the cloud: every sentence makes a round trip to a server. Phonon runs on your own device instead. Your text stays there and the voice works without a network. We’ve also opened the weights. Phonon 31m is Apache 2.0, so you can use it for free, even in a commercial product. The other models are CC BY-NC, so they’re free for non-commercial projects. If you’re building something commercial with those, pricing is based on your number of users, not how much speech you generate.