ACE-Step
ACE Studio & StepFun class A live
Open-weights (Apache-2.0) music foundation model co-led by ACE Studio and StepFun; fast local vocals+instrumental synthesis with a technical report.
Layer 1 — factual axes
| API & price | no (community-hosted; no official API) | secondary | source ↗ 2026-07-04 |
|---|---|---|---|
| Max length | up to ~4 min | official | source ↗ 2026-07-04 |
| Vocals | vocals + instrumental | official | source ↗ 2026-07-04 |
| Weights | open · Apache-2.0 | official | source ↗ 2026-07-04 |
| Free tier | open self-host | official | source ↗ 2026-07-04 |
| Commercial rights | Commercial use permitted (Apache-2.0); disclose AI involvement | official | source ↗ 2026-07-04 |
Layer 2 — output quality
No independent measure yet. We publish a quality figure only when a named external benchmark ranks this model — we don’t invent one.
Open-weights (Apache-2.0) music foundation model co-led by ACE Studio and StepFun; fast local vocals+instrumental synthesis with a technical report.