Introducing Phonon ・ Our first open, on-device TTS model

Blog

What can we help youfind today?

Discover our articles and videos

October 26, 20265 minProduct

Gradium and Yampa partner on voice AI agents for customer experience

Gradium's voice models now run natively inside Yampa, the agentic platform enterprises use to build, deploy and supervise customer care agents, in SaaS on EU infrastructure or on-premise.

Discover
October 21, 20264 minAnnouncement

Gradium releases Phonon, an open-source text-to-speech model that runs on any device

Trained on NVIDIA GPUs, Phonon generates natural speech locally in as little as 64.5 MB, on phones, laptops, embedded hardware and in the browser.

Discover
October 20, 20268 minAnnouncement

Open-Sourcing Phonon: A Suite of Frontier On-Device TTS Models

Today, we're open-sourcing Phonon, now a family of 31m and 40m parameter text-to-speech (TTS) models that set a new standard for naturalness and accuracy on-device.

Discover
October 19, 20263 minAnnouncement

Gradium is now available on Eden AI

Eden AI is an AI gateway: one API for 500+ models across LLMs, speech, vision and translation, with routing, fallbacks and a dedicated EU endpoint for European data residency. Gradium's Text-to-Speech, Speech-to-Text and speech translation are now available through that API, pinned to the EU region.

Discover
October 7, 20266 minProduct

1,000+ new voices, our most natural set yet

The Gradium voice catalog grows from ~380 to 1.4k voices. The 1,000+ new voices cover 28 accents across English, French, Spanish, German and Portuguese, cast for customer service, narration, ads and characters. Listen to 62 of them, and see how they were chosen.

Discover
October 1, 20263 minProduct

Why we built the fastest robust TTS model

Our latest Text-to-Speech model takes under 50ms for the first audio chunk to arrive. Choosing a fast model does not have to come with cutting corners for model robustness: it improves naturalness and expressivity while retaining our strengths on hard cases like phone numbers and alphanumeric text.

Discover
September 29, 20269 minEngineering

Giving voice agents a voice that adapts to context

Most voice agents speak with one preselected voice, whoever is on the line. Once a voice can be created from a text description, the voice becomes another property your code computes from context. This article builds the full pipeline: classify the message, map the signals to a Voice Design prompt, resolve it to an approved voice on the hot path, and design the missing ones in the background.

Discover
September 9, 20265 minEngineering

How a benchmark change produced a faster TTS model

On June 3, 2026, Gradium's time to first audio on the Coval TTS leaderboard moved from 171.9 ms to 429.6 ms. No model had shipped and no serving infrastructure had changed. What changed was the measurement: Coval had started counting the silence at the start of the stream.

Discover
September 9, 20263 minAnnouncement

Gradium now available for free on LiveKit Inference

Gradium Text-to-Speech is now available on LiveKit Inference, free until Oct. 9. Gradium TTS is designed for conversational use cases, with voice cloning, low latency (below 250ms TTFA), and robust pronunciation on difficult cases.

Discover
September 7, 20266 minProduct

Launching Voice Design: prompt the voice your agent needs

Developers building voice agents ask us for voices matched to the use case in front of them: a Québécoise receptionist for a Montréal dealership, a Paulista support agent for a São Paulo fintech, a narrator in his sixties with the authority of a lecture hall. Briefs outnumber any catalog. Voice Design starts from a prompt: write one or two sentences, get complete new voices back in seconds, keep the one you want.

Discover