Meta this week announced the release of Muse Spark Open. The company calls it the “the most capable US open-weight model to date.” Meta worked with Apple to bring Muse Spark Open to the Mac Ultra. The model can run on a desktop setup with two 512GB Apple M5 Ultra Mac Studios running the latest MLX framework.
Muse Spark Open is a natively multimodal model with 816 billion total parameters (42 billion active) and a 1 million-token context window. It is designed for coding and agentic work, and Muse says it excels at long-horizon tasks, complex software engineering, and multi-step reasoning.
The new Muse model was tuned to run on Mac Studio, and Meta says the Mac Studio paired with Muse Spark Open is the “best way to run a powerful model on your own desktop.”
Apple’s unified memory architecture lets the M5 Ultra’s integrated GPU use up to 512 GB per Mac Studio, so two machines can hold an entire model. And the chip’s 1.2 TB/s of memory bandwidth is fast enough to read the small slice each token needs. The result is two Mac Studios behave like one supercomputer with a terabyte of unified memory.
Meta and Apple cooperated with Apple to bring Muse Spark Open to the Mac, and tMeta CEO Mark Zuckerberg thanked Apple CEO John Ternus for working with Meta, and Apple CEO John Ternus also offered his congratulations to the team:
While the 512GB Mac Studio is not available as of yet, it is expected to be coming later this month. The 256GB Mac Studio is priced over $10,000, so developers can expect to pay even more dearly for the 512GB model.
The model is available through API platforms at Baseten, Fireworks AI, Groq, Modal, Nebius, OpenRouter, and Together AI, with model weights downloadable from Amazon SageMaker AI, Google Cloud Model Garden, Hugging Face, and Microsoft Foundry Models. Muse Spark Open is free to download and has a license allowing limited commercial use.
(Via MacRumors)