ACE Music v1 edges past Suno on the AI music leaderboard, but not at metal

What's going on

Suno has long been the undisputed leader in AI music. Now a relatively unknown rival has narrowly overtaken it, at least on one closely watched leaderboard. ACE Music v1 from ACE Studio sits at the top of the vocal music leaderboard run by research firm Artificial Analysis. It scores 1,160 Elo points, while Suno v6 scores 1,144. Tech outlet Decrypt put the two models head to head.

ACE Music v1 runs in the browser on ACE Studio's website. There's a limited free tier and paid subscriptions. The model weights aren't publicly available, and there's no public application programming interface (API).

How the leaderboard works

The benchmark is called AA-Music-Vocal v1.1 and rates AI songs with vocals. Several models get the same prompt, meaning the same text description. Listeners hear the results without knowing which model made which song, then pick their favorite. Many of these matchups add up to an Elo rating, a points system borrowed from chess: beat strong opponents and you climb.

Decrypt adds its own caveat: the lead is slim, and the confidence intervals overlap. Those are the ranges of uncertainty around each score. So statistically, it isn't certain that ACE really is better. On the separate leaderboard for instrumental music, Suno is still ahead.

Hands-on: strong in the mainstream, weak at metal

In Decrypt's test, ACE Music consistently produced more melodic, more coherent songs in popular styles. The vocals usually sounded more natural. Typical AI glitches showed up less often: singers struggling to pronounce their own lyrics, heavy-handed Autotune, or made-up words filling the gaps.

Decrypt is especially impressed by the song endings. Suno sometimes throws in strange noises, pointless repetition or abrupt shifts at the end. ACE, by contrast, usually held the structure together right through to a clean finish. That matters more than it sounds: a catchy chorus is relatively easy. The hard part is carrying a musical idea through an entire song, even after the lyrics have run out.

With unusual genres, Suno came out ahead. In a melodic death metal test, ACE kept delivering a woman singing clearly and pleasantly. The aggressive vocals the genre demands never appeared. According to Decrypt, ACE generally confuses metal subgenres. Suno delivered more creative arrangements in the right heavy style. Decrypt stresses that these are subjective impressions, not a controlled benchmark. Winning a leaderboard doesn't automatically make a model the better choice for every musician.

More production tool than song vending machine

According to Decrypt, the most interesting thing about ACE is the workflow. The "Idea" feature turns a rough concept into lyrics and a structured composition. It labels each section of the song and describes how it should be arranged. You can refine this material instead of generating brand-new songs over and over.

The v1.1 Preview goes further, generating a score before any audio. The developers explain:

"Each generation is a new performance, so the sound may vary even if the score stays the same."

You can edit melodies and chords, regenerate performances and export MIDI files. MIDI is a digital notation format that music software can work with directly. Stem separation also lets you split vocals and instruments into separate tracks for further editing.

A Japanese hobby musician describes what this looks like in practice on the blogging platform note.com. He discovered ACE Studio in summer 2026. He records his own songs with vocals and guitar in his music software (DAW) and imports them into ACE Studio. The "Music Enhancer" feature recognizes the song and suggests a prompt, which he tweaks. The result is a full arrangement with AI vocals. He then uses stem separation to replace the AI vocals with his own voice. An arrangement of that quality would have taken him a lot of time by hand, he writes. With ACE it takes just a few minutes, and the program comes up with ideas he wouldn't have thought of himself. He explicitly mentions the unresolved copyright questions. He sees the AI as a stand-in for a production team he can't afford.

Open source: ACE-Step now, ACE Music Flash later

The flagship stays closed, but ACE Studio is running an open-source strategy in parallel. Together with Chinese AI company StepFun, it has already released ACE-Step 1.5. That's a separate model family with public code and weights. It runs on your own hardware, but according to Decrypt it's weaker than ACE Music v1. For late 2026, the developers announce:

"We plan to release ACE Music v1 Flash as open source in late 2026."

This version is meant to balance quality, generation speed and hardware requirements. The sources don't give concrete hardware specs yet.

If you want to use songs from the flagship commercially, you need a paid subscription. ACE-Step has a separate free way to generate songs. ACE Studio was founded in 2018 and originally synthesized singing voices from MIDI notes and lyrics, essentially a kind of virtual singer.

Background: Suno under legal pressure

The narrow loss of the top spot hits Suno at a turbulent time. According to Rolling Stone, the company has just launched its v6 model family. Suno says it was trained "from the ground up" on licensed data from Warner Music Group (WMG), plus user data and the team's "accumulated learnings". WMG dropped its lawsuit last November in exchange for a licensing partnership. BMG and distributor Believe (TuneCore) have since signed on as partners too. Suno is shutting down its old models, which were trained on music scraped from the web without permission. Since September, Suno has been adding audio watermarks to its songs and capping monthly downloads. In June, the company raised $400 million at a $5.4 billion valuation.

That's not enough for Sony Music and Universal Music Group. According to Variety, they've filed a new 45-page lawsuit in federal court in Massachusetts. Their argument: v6 was also trained on outputs from earlier Suno models. Training a new model on the outputs of an infringing model doesn't cure the infringement, they say, it "launders" it. The labels write:

"V6 is not a fresh start but the fruit of the same poisonous tree."

The labels cite 60,202 infringed recordings and say that's only a small fraction of the total. Suno calls the allegations "fundamentally flawed, factually and legally". On top of that, there's a $1 billion lawsuit from publisher Round Hill and a proposed class action led by singer Jason Isbell.

The big picture

A challenger beating Suno on a blind-test leaderboard shows that the AI music market has gotten tighter. But the lead isn't statistically solid, and Suno remains stronger for instrumental music and extreme genres. What musicians will probably care about more is ACE's approach: the score, MIDI export and stem separation turn the tool into a production assistant rather than a song lottery. For tinkerers, the announced open-source Flash version is the exciting part. Whether and when it actually ships, and how close it gets to the flagship, is still unclear. Also unclear is what data ACE Music was trained on. The sources say nothing about it, even though that's exactly the question currently dragging Suno into court.