acestep-xl-sft

Model Details

This is the XL (4B) SFT variant of ACE-Step 1.5 — a supervised fine-tuned model with ~4B parameters. SFT provides higher audio quality with CFG (Classifier-Free Guidance) support for fine-grained prompt adherence control.

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.
• 🎯 CFG Support: Fine-tune prompt adherence with guidance scale control.
• 🔮 Highest Quality: SFT + 4B parameters = the highest quality variant.

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 ACE-Step/acestep-v15-xl-sft --local-dir ./checkpoints/acestep-v15-xl-sft

# Run with Gradio UI
python acestep --config-path acestep-v15-xl-sft

Model Zoo

XL (4B) DiT Models

LM Models (all compatible with XL)

Acknowledgements

This project is co-led by ACE Studio and StepFun.

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}
}