ACE-Step 1.5 XL — Turbo (4B DiT) BF16

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Model Details

This is the BF16 version of ACE-Step/acestep-v15-xl-turbo — the XL (4B) Turbo variant of ACE-Step 1.5. This BF16 conversion reduces memory usage while maintaining near-identical quality to the original model. It is a distillation-accelerated model that generates high-quality audio in just 8 steps, combining the speed of turbo with the quality of the 4B architecture.

XL Architecture

GPU Requirements

All LM models (0.6B / 1.7B / 4B) are fully compatible with XL.

Key Features

• 💰 Commercial-Ready: Trained on legally compliant datasets. Generated music can be used for commercial purposes.
• • 📚 Safe Training Data: Licensed music, royalty-free/public domain, and synthetic (MIDI-to-Audio) data.
  • • ⚡ Fast: 8-step inference — the fastest XL variant.

    • • 🔮 Higher Quality: 4B parameters provide richer audio quality than 2B turbo.

      • • 🧠 BF16 Precision: Converted to BF16 for reduced VRAM usage and faster inference, with negligible quality loss.

        • Quick Start

      • # Install ACE-Step
        git clone https://github.com/ace-step/ACE-Step-1.5.git
        cd ACE-Step-1.5
        pip install -e .
        
        # Download this model
        huggingface-cli download marcorez8/acestep-v15-xl-turbo-bf16 --local-dir ./checkpoints/acestep-v15-xl-turbo-bf16
        
        # Run with Gradio UI
        python acestep --config-path acestep-v15-xl-turbo-bf16
        

        Model Zoo

        XL (4B) DiT Models

        DiT Model	CFG	Steps	Quality	Diversity	Tasks	Hugging Face	ModelScope
        acestep-v15-xl-base	✅	50	High	High	All (extract, lego, complete)	Link	Link
        acestep-v15-xl-sft	✅	50	Very High	Medium	Standard	Link	Link
        acestep-v15-xl-turbo	❌	8	Very High	Medium	Standard	Link	Link
        acestep-v15-xl-turbo-bf16	❌	8	Very High	Medium	Standard	This repo	—

        LM Models (all compatible with XL)

        LM Model	Params	Audio Understanding	Composition	Hugging Face	ModelScope
        acestep-5Hz-lm-0.6B	0.6B	Medium	Medium	Link	Link
        acestep-5Hz-lm-1.7B	1.7B	Medium	Medium	Included in main	Included in main
        acestep-5Hz-lm-4B	4B	Strong	Strong	Link	Link

        Acknowledgements

        This project is co-led by ACE Studio and StepFun. The BF16 conversion was done by marcorez8 to make the model more accessible to the community.

        Citation

        @misc{gong2026acestep,
          title={ACE-Step 1.5: Pushing the Boundaries of Open-Source Music Generation},
          author={Junmin Gong, Yulin Song, Wenxiao Zhao, Sen Wang, Shengyuan Xu, Jing Guo},
          howpublished={\url{https://github.com/ace-step/ACE-Step-1.5}},
          year={2026},
          note={GitHub repository}
        }