Meta open-sources Muse Spark Open: 816B MoE that runs on two Mac Studios
op7418 · x · 2026-10-16
Meta released Muse Spark Open, billed as the most capable US open-weight model, deeply optimized on Apple's MLX framework.
Key specs:
- 816B total parameters, 42B active (MoE)
- 1T token context window
- Native text, image, video, and audio input
- Runs locally on two M5 Ultra Mac Studios (512GB unified memory each, 1TB combined, 1.2 TB/s bandwidth)
Benchmarks trade wins with GLM-5.3 and Kimi K3: leads on JobBench (61.8), MCP-Atlas (89.2), HLE-Diamond (26.1), ZeroBench (50.0), SimpleQA (73.6); trails on GDPval-AA v2, Terminal-Bench 2.1, and DeepSWE.
Related event: Meta Open-Sources Muse Spark Open with 816B Parameters and 1M Context(39 posts)→
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