Model reference · open weights

acestep-shift1

Audio ACE-Step Music / audio 1 build Open weights 257 dl/mo

acestep-shift1 is an open-weight audio or speech model from ACE-Step. acestep-v15-turbo-shift1 (BF16) weighs 4.8 GB; the smallest configuration that runs it is RTX 3060 12 GB.

  • ACE-Step/acestep-v15-turbo-shift1 is a 2.4B parameter text-to-audio model developed by ACE-Step for music generation.
  • It supports over 50 languages and operates under the MIT license.
  • The model is designed to run on consumer hardware with less than 4GB of VRAM and generates full songs in under 10 seconds on an RTX 3090.

Summary of the ACE-Step/acestep-v15-turbo-shift1 model card, 2026-10-01

What it is

Released byACE-Step
Released2026-01-29
Parameters2.4B
VRAM4.8 GB for the weights

What it runs on

Memory and cards for acestep-v15-turbo-shift1 (BF16)

4.8 GBweights, file size
1.6 GBruntime overhead
CardOne streamMemory
RTX 3060 12 GBfits11.6 GB
RTX 4060 Ti 16 GBfits15.4 GB
RTX 3090 24 GBfits23.4 GB
RTX 4090 24 GBfits23.4 GB
RTX 5090 32 GBfits31.0 GB
L40S 48 GBfits44.0 GB
A100 80 GBfits78.2 GB
H100 80 GBfits78.1 GB
RTX PRO 6000 Blackwell 96 GBfits93.8 GB
DGX Spark (GB10) 128 GB unifiedfits107 GB
H200 141 GBfits138 GB
B200 180 GBfits176 GB

From the model card

What ACE-Step says about acestep-shift1

Read the model card

Model Details

🚀 ACE-Step v1.5 is a highly efficient open-source music foundation model designed to bring commercial-grade music generation to consumer hardware.

Key Features

  • 💰 Commercial-Ready: Unlike many models trained on ambiguous datasets, ACE-Step v1.5 is designed for creators. You can strictly use the generated music for commercial purposes.
  • 📚 Safe & Robust Training Data: The model is trained on a massive, legally compliant dataset consisting of:
    • Licensed Data: Professionally licensed music tracks.
    • Royalty-Free / No-Copyright Data: A vast collection of public domain and royalty-free music.
    • Synthetic Data: High-quality audio generated via advanced MIDI-to-Audio conversion.
  • ⚡ Extreme Speed: Generates a full song in under 2 seconds on an A100 and under 10 seconds on an RTX 3090.
  • 🖥️ Consumer Hardware Friendly: Runs locally with less than 4GB of VRAM.

Technical Capabilities

🌉 At its core lies a novel hybrid architecture where the Language Model (LM) functions as an omni-capable planner: it transforms simple user queries into comprehensive song blueprints—scaling from short loops to 10-minute compositions—while synthesizing metadata, lyrics, and captions via Chain-of-Thought to guide the Diffusion Transformer (DiT). ⚡ Uniquely, this alignment is achieved through intrinsic reinforcement learning relying solely on the model's internal mechanisms, thereby eliminating the biases inherent in external reward models or human preferences. 🎚️

🔮 Beyond standard synthesis, ACE-Step v1.5 unifies precise stylistic control with versatile editing capabilities—such as cover generation, repainting, and vocal-to-BGM conversion—while maintaining strict adherence to prompts across 50+ languages. This paves the way for powerful tools that seamlessly integrate into the creative workflows of music artists, producers, and content creators. 🎸

  • Developed by: [ACE-STEP]
  • Model type: [Text2Music]
  • Language(s): [50+ languages]
  • License: [MIT]

Evaluation

🏗️ Architecture

🦁 Model Zoo

DiT Models

DiT ModelPre-TrainingSFTRLCFGStepRefer audioText2MusicCoverRepaintExtractLegoCompleteQualityDiversityFine-TunabilityHugging Face
acestep-v15-base✅❌❌✅50✅✅✅✅✅✅✅MediumHighEasyLink
acestep-v15-sft✅✅❌✅50✅✅✅✅❌❌❌HighMediumEasyLink
acestep-v15-turbo✅✅❌❌8✅✅✅✅❌❌❌Very HighMediumMediumLink
acestep-v15-turbo-rl✅✅✅❌8✅✅✅✅❌❌❌Very HighMediumMediumTo be released

LM Models

LM ModelPretrain fromPre-TrainingSFTRLCoT metasQuery rewriteAudio UnderstandingComposition CapabilityCopy MelodyHugging Face
acestep-5Hz-lm-0.6BQwen3-0.6B✅✅✅✅✅MediumMediumWeak✅
acestep-5Hz-lm-1.7BQwen3-1.7B✅✅✅✅✅MediumMediumMedium✅
acestep-5Hz-lm-4BQwen3-4B✅✅✅✅✅StrongStrongStrong✅

🙏 Acknowledgements

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

📖 Citation

If you find this project useful for your research, please consider citing:

@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}
}

Quoted from the model card on Hugging Face. The full card is behind the Hugging Face link above.

Running it yourself

Run it on a rented GPU

Rent a machine by the hour. How to run this model is on its model card.

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