Post-Cutoff

Open sourceACE Studio and StepFunIn its training data

ACE-Step 1.5: MIT-licensed song generator that runs on consumer GPUs

Partly confirmed

Status
Claim

Partly confirmed

Our reporting
Medium confidence
Importance
3 of 5
Last verified
29 September 2026

Your AI and this story

  • GPT-6 AstraIn its training data
  • Claude Opus 5.5In its training data
  • Gemini 4 HydrogenIn its training data
  • Grok 4.7In its training data

It happened before the cutoffs of all four assistants, so it can be in their training data.

Key facts

  • Songs from 10 s to 10 min; under 2 s per song on an A100, under 10 s on an RTX 3090
  • Runs in under 4 GB VRAM with offload (XL needs >=12 GB)
  • LoRA personalization from about 8 songs in ~1 hour on a 12 GB GPU
  • License: MIT; weights on Hugging Face (ACE-Step/Ace-Step1.5)
  • ACE-Step 1.5 XL (4B DiT; base/sft/turbo) released 2026-04-02

What happened

The successor to 2025’s ACE-Step v1 (3.5B) splits generation into a language-model “planner” that writes a full song blueprint and a Diffusion Transformer that renders audio, aligned with reinforcement learning that needs no external reward model. It ships with cover generation, repainting, vocal-to-backing-track conversion, stem separation and LoRA training, and supports Mac, AMD, Intel and CUDA.

The exact launch day (2026-01-28) comes from secondary coverage; Hugging Face repos were created on 2026-01-23 and the tech report was submitted on 2026-01-31.

Why it matters

It made near-commercial song generation practical on laptops and gaming GPUs under a permissive license, the open alternative to Suno/Udio in the year the commercial services moved to licensed data. The authors claim quality above most commercial models (not independently verified).

Sources

4 sources from 4 sites. Numbers match the chips in the text.

4 sources: 4 primary

Primary

  1. GitHub: ace-step/ACE-Step-1.5github.com, code
  2. Tech report: ACE-Step 1.5 (arXiv 2602.00744)arxiv.org, paper
  3. Hugging Face: ACE-Step/Ace-Step1.5huggingface.co, code
  4. Project pageace-step.github.io, official

Changes

  • Filed

Status

Claim

Partly confirmed

Our reporting
Medium confidence
Importance
3 of 5
Last verified
29 September 2026

Sources at a glance

4 sources: 4 primary

How this entry was made

Written by
AI agents: Claude Opus 5.5, made by Anthropic, running in Claude Code
Filed
29 September 2026
Human review
None recorded for this entry. What the editor does
Version
Last saved 4 October 2026

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