Phonon

Phonon

Gradium
+
+

Related Products

  • LTX
    182 Ratings
    Visit Website
  • Runpod
    230 Ratings
    Visit Website
  • LM-Kit.NET
    29 Ratings
    Visit Website
  • IONOS Cloud GPU Servers
    45,340 Ratings
    Visit Website
  • Nexo
    18,780 Ratings
    Visit Website
  • Compute with Hivenet
    4 Ratings
    Visit Website
  • AnalyticsCreator
    46 Ratings
    Visit Website
  • Gemini Enterprise Agent Platform
    1,161 Ratings
    Visit Website
  • Fraud.net
    56 Ratings
    Visit Website
  • Iru
    1,389 Ratings
    Visit Website

About

Muse Spark Open is an open-weight, natively multimodal language model for developers and organizations building AI applications, coding systems, and agentic workflows. The released model has 816 billion total parameters, 42 billion active parameters, and a 1-million-token context window. Teams can download the model weights, run inference through supported engines such as vLLM, SGLang, TensorRT-LLM, Hugging Face Transformers, Apple MLX, llama.cpp, or Unsloth, and customize the model using PyTorch. It supports long-context reasoning, software engineering, coding, tool use, and multimodal inputs. Deployment options include cloud inference through listed API providers or self-hosting on compatible GPU systems; Meta documents a desktop setup using two Apple M5 Ultra Mac Studio computers. The model is released under the Muse Model License with limited commercial terms.

About

Phonon is an open-weight text-to-speech (TTS) model and inference runtime for developers adding speech generation to applications that need local, offline audio. It converts text into spoken audio and can stream speech as it is generated. The runtime provides Rust and Python interfaces, a Swift package for iOS and macOS, JavaScript for browsers, and Android libraries; it can also run as a self-hosted server with an OpenAI-compatible API. Depending on the model variant, it supports English, French, German, Spanish, and Portuguese. Phonon is intended for developers integrating speech into mobile, desktop, web, embedded, and server applications, including offline or privacy-sensitive use cases. The 31-million-parameter English model weights use the Apache 2.0 license; 40-million-parameter language-specific and multilingual weights use CC BY-NC 4.0. The runtime code is separately available under Apache 2.0 or MIT.

Platforms Supported

Windows Supported
Mac Supported
Linux Supported
Cloud Supported
On-Premises Supported
iPhone Not Supported
iPad Not Supported
Android Not Supported
Chromebook Not Supported

Platforms Supported

Windows Supported
Mac Supported
Linux Supported
Cloud Not Supported
On-Premises Supported
iPhone Supported
iPad Supported
Android Supported
Chromebook Not Supported

Audience

AI developers, machine learning engineers, software engineers, AI researchers, enterprise development teams, and organizations seeking customizable open-weight multimodal models for local inference, autonomous agents, complex coding, and long-context AI applications

Audience

Developers and product teams building mobile, desktop, web, embedded, or server applications that need text-to-speech, including offline or privacy-sensitive use cases.

Support

Phone Support Not Supported
24/7 Live Support Not Supported
Online Not Supported

Support

Phone Support Not Supported
24/7 Live Support Not Supported
Online Not Supported

API

Offers API Not Supported

API

Offers API Supported

Screenshots and Videos

Screenshots and Videos

No images available

Pricing

$0
Model weights are available at no charge under the Muse Model License, which has limited commercial-use terms. Hosted inference providers set their own usage prices.
Free Version Supported
Free Trial Not Supported

Pricing

No information available.
Free Version Supported
Free Trial Not Supported

Reviews/Ratings

Overall 5.0 / 5
ease 5.0 / 5

Reviews/Ratings

Overall 0.0 / 5
ease 0.0 / 5
features 0.0 / 5
design 0.0 / 5
support 0.0 / 5

This software hasn't been reviewed yet. Be the first to provide a review:

Review this Software

Pros & Cons from Real Users

Pros

  • Meta finally opened up a genuinely frontier-level Muse model. The 1M-token context window and 42B active parameters make it strong enough for large repos, long agent sessions, multimodal work, and complex coding without feeling like a stripped-down open model. The local deployment story is also a huge deal. Being able to run something this capable on two M5 Ultra Mac Studios is impressive, especially for teams that want more control over data, infrastructure, and customization. I also like how much of the stack is open around it. Muse Spark Open works with MLX, vLLM, SGLang, TensorRT-LLM, Transformers, llama.cpp, and Unsloth, and Meta is making the weights available through Hugging Face, SageMaker, Google Cloud Model Garden, and Microsoft Foundry.

Cons

  • Even though it is technically desktop-capable, needing two M5 Ultra Mac Studios for the full local experience is still a serious setup, so most developers will probably use hosted inference instead.

Training

Documentation Supported
Webinars Not Supported
Live Online Not Supported
In Person Not Supported

Training

Documentation Supported
Webinars Not Supported
Live Online Not Supported
In Person Not Supported

Company Information

Meta
Founded: 2004
United States
research.meta.ai/blog/muse-spark-open

Company Information

Gradium
Founded: 2025
France, United States
gradium.ai/phonon

Alternatives

Alternatives

Qwen3-TTS

Qwen3-TTS

Alibaba
Piper TTS

Piper TTS

Rhasspy
Simba 3.2

Simba 3.2

Speechify
Inkling

Inkling

Thinking Machines Lab
Chirp 3

Chirp 3

Google

Categories

Categories

Integrations

Hugging Face Supported
Baseten Supported
Fireworks AI Supported
Groq Supported
Modal Supported
Nebius Supported
OpenRouter Supported
Together AI Supported
vLLM Supported

Integrations

Hugging Face Supported
Baseten Not Supported
Fireworks AI Not Supported
Groq Not Supported
Modal Not Supported
Nebius Not Supported
OpenRouter Not Supported
Together AI Not Supported
vLLM Not Supported
Claim Muse Spark Open and update features and information
Claim Muse Spark Open and update features and information
Claim Phonon and update features and information
Claim Phonon and update features and information