Project AURIONAI Use-Cases Research & Innovation
StepFun
music and audio

ACE-Step 1.5

Open MIT music model jointly developed by StepFun and ACE Studio (community source), with a v1.5 XL Turbo version.

StepFunStepFunChinaACE StudioACE Studio
image.
Levelmodel
Classmusic and audio
Parametersnot in the notes
Contextnot in the notes
Released31 Jan 2026
Opennessopen weights permissive
Runs onconsumer GPU
Statusactive

From the model's own page; who made each picture and where it comes from are listed on the Image Credits page.

Lineage

successor
ACE-Step v1 to ACE-Step 1.5: successor, high confidenceACE-Step v1ACE-Step v1StepFunACE-Step 1.5ACE-Step 1.5StepFun, Jan 2026
StepFunACE-Step v1 is the parent (successor)high confidencenotes
Where this comes from
Parent and child relations from model cards, Hugging Face base_model fields and the genealogy tables of the research notes. The tree shows two generations each way, 2 models. Confidence and evidence are the notes' own.

R&D Topics

Text-to-music and song generationexemplar

Identity

Developer
StepFun, ACE Studio
Family
not in the notes
Released
31 Jan 2026 sourcesregistry date
Weights published
–
Record checked
10 Oct 2026
Where this comes from
Developer and dates from the research notes. Release date is the vendor's public announcement; weights date is when open weights were published.

Architecture and Size

Architecture
hybrid LM planner (Qwen3 0.6B / 1.7B / 4B) plus DiT
Total parameters
– sources
Active parameters
–
Checkpoint parameters
–
Context length
not in the notes
Input
text
Output
audio
Where this comes from
Parameter counts as the developer states them. Where the checkpoint holds a different total, both are shown (register A16).

Openness and Access

Openness
open weights permissive
Licence
MIT License sources
Access routes
open weights download
Where this comes from
The licence file governs over registry tags and aggregator labels.

Deployment

Runs on
consumer GPU
Footprint
Under 4 GB VRAM
Runtimes
not in the notes
Where this comes from
Deployment tiers and runtimes as named in the notes. Footprint is the notes' figure, not a measurement by AURION.

Indonesia

Indonesian support
not stated
Regional languages
not in the notes
Jakarta hosting
unknown
Languages
50+ languages; Indonesian not confirmed
Where this comes from
Indonesia fields are carried on every model; unknown is an allowed value.

Benchmark Results

The notes record no benchmark result for this model.

Industry Use Cases

No industry use case links this model.

Sources

  1. huggingface.co/ACE-Step/Ace-Step1.5 https://huggingface.co/ACE-Step/Ace-Step1.5
  2. Text-to-Audio Models – Hugging Face huggingface.co https://huggingface.co/models?pipeline_tag=text-to-audio&sort=trending
  3. ACE-Step: Open Source Music Generation Models by StepFun | ComfyUI Wiki comfyui-wiki.com https://comfyui-wiki.com/en/models/ace-step

To cite this page: Project AURION, AI Use-Cases Research & Innovation, "ACE-Step 1.5", https://aurion.semai.id/models/stepfun-ace-step-1-5/, records of October 2026.