RoEx

TL;DR

RoEx Automix is an AI mixing and mastering tool. You upload your stems and it returns a balanced, release-ready track in minutes. It’s built for indie artists and bedroom producers who record their own parts but can’t mix them. It does fast, hands-off mixing better than most rivals, and the first download is free. It does less than a desktop plugin when you want manual control over every move.

What is RoEx?

RoEx is a British company that makes AI mixing and mastering tools, built on audio research from Queen Mary University of London. Its main product, Automix, takes the raw stems from your session and returns a finished mix and master without an engineer or a studio.

RoEx sits between a one-click mastering service and a full DAW. It automates more than mixing by hand, and it does more than a master-only tool. Two sibling products round it out: Mix Check Studio for analysis, and the Tonn API for developers.

How RoEx Automix works

The flow is short. You create a project and upload your stems, the separate tracks for drums, bass, guitars, vocals, and so on. Automix analyzes each one, then balances levels, EQ, panning, and dynamics across the whole mix. It applies a master so the track hits streaming loudness.

You preview the full result in your browser before you spend anything. When you’re happy, you download the file, or export an Ableton Live Set or a DAWproject file to keep editing in your own DAW. The free tier covers the upload, mix, and preview. You spend a credit only when you download.

Standout features

Five things stood out after mixing my own songs:

• First mix free: You hear Automix on your own track before paying a cent, which no other major AI mixer offers.
• 32-track mixing: Pro handles full-band arrangements, not only four-stem demos, so dense sessions come back balanced.
• Reference track mastering: Feed it a song you love and the master matches its tone, so your release sits next to commercial tracks.
• DAW export: An Ableton Live Set or DAWproject file means the AI mix is a starting point you can still shape by hand.
• Mix Check Studio: A second product reads your finished file and tells you what’s off, like a quick engineer’s opinion before release.

Where RoEx Automix falls short

Three things to know before you commit:

• Your recordings set the ceiling: Automix balances what you give it. Muddy or clipped stems come back as a muddy mix, so your tracking quality still caps the result.
• Credits add up: At $5.99 a download, mixing ten songs costs more than a month of Pro. If you release often, the per-credit model is the wrong plan.
• Three products, one brand: Automix, Mix Check Studio, and the Tonn API live under RoEx with separate sites. It took me a minute to work out which one I needed.

Pricing breakdown

RoEx Automix runs on a freemium, pay-as-you-go model. Here is what each tier costs and who it fits:

Plan	Price	What you get	Best for
Free	$0	Upload stems, create mixes, preview results, plus 1 download credit	Testing Automix on your own song
Download credit	$5.99 each	One downloadable mix or master, no subscription	Occasional one-off releases
Automix Pro	$14.99/mo	Unlimited downloads, 32-track mixing, Ableton Live Set and DAWproject export, reference mastering, unlimited audio cleanup	Anyone releasing music regularly

Prices match in pounds and euros (£5.99 / €5.99 per credit, £14.99 / €14.99 a month for Pro). Pricing changes from time to time, so check the current plans on the Automix pricing page before you subscribe.

The free credit is the part I rate highest. Most AI mixers make you pay before you hear the output on your music. RoEx lets you mix, preview, and download one full track for nothing.

Who should use RoEx Automix?

Choose RoEx if you record your own parts but freeze up at the mixing stage. You write, track, and arrange, then stall turning raw stems into something that sounds finished. Automix gets you past that in minutes.

Choose RoEx if you release often and need speed. A single you’d send to an engineer for a week comes back mixed and mastered the same afternoon, for a fraction of what an engineer charges. Pro works out cheaper by your second or third track a month.

Choose RoEx if you want to learn mixing, not skip it. Run your mix through Mix Check Studio, read what it flags on tonal balance and loudness, and your next session improves. Used this way, it’s a teacher as much as a shortcut.

Who should skip it

Skip Automix if you mix by hand and want control over every band and every move. A desktop plugin like Ozone gives you that, and an AI pass will feel like it’s making calls you’d rather make yourself. Same if you’re finishing a flagship release with real budget, where a human engineer earns the spend.

RoEx Automix vs the alternatives

How RoEx compares to the tools it’s measured against:

• vs LANDR — LANDR masters only, per credit or subscription. RoEx adds full stem mixing and analysis.
• vs BandLab Mastering — BandLab masters free but stops there. RoEx mixes your stems and gives feedback too.
• vs Ozone — iZotope’s Ozone is a hands-on desktop plugin. RoEx is cloud and automated, trading control for speed.
• vs MasterChannel — MasterChannel masters. RoEx adds the mix stage around it.

The line that separates RoEx: it mixes your raw stems, not only masters a finished track. For the full field, read my 4 best AI mixing and mastering tools roundup.

Frequently Asked Questions

Is RoEx Automix free?

You can use Automix free to upload stems, create mixes, and preview the result. Every new account gets 1 free download credit, so you download one finished track at no cost before you decide to pay.

How much does RoEx Automix cost?

Extra downloads are $5.99 each as one-off credits. Automix Pro is $14.99 a month for unlimited downloads, 32-track mixing, DAW export, reference mastering, and unlimited audio cleanup.

Can I use RoEx Automix mixes commercially?

Yes. Tracks you mix and master with Automix are yours to release and sell. Check RoEx’s current terms for any specifics tied to your plan.

What file formats does RoEx Automix export?

Automix delivers standard audio files. On Pro, it also exports an Ableton Live Set and a DAWproject file, so you reopen the mix in Ableton, Bitwig, Studio One, or another DAWproject-compatible DAW.

What is RoEx Mix Check Studio?

It’s RoEx’s analysis tool. You upload a finished mix or master and it reports on tonal balance, dynamics, and loudness, with the first report free and no sign-up. I didn’t run my Automix tracks through it during this test, but I’d recommend doing so before you release.

Does RoEx Automix replace a mixing engineer?

For demos and indie releases, it gets you most of the way at a fraction of the cost. For a flagship single where the budget and the arrangement justify it, a human engineer still wins. I use both, depending on the stakes.

The verdict

Automix handles the technical heavy lifting that stops most non-engineers cold: EQ balance, compression, stereo imaging, and loudness. You get those through a few clicks instead of years of training.

A human engineer still wins on the creative calls, unusual arrangements, and major releases where the budget and the relationship pay off. For most independent artists, Automix covers 80 to 90 percent of your mixing and mastering at a fraction of the cost and time.

It only replaces you if you hand over the calls. Keep your hands on the arrangement, the taste, and the final yes or no, and it stays an instrument. That balance, plus the free first download, is why I rate it 4.5 out of 5.

Try RoEx Automix

Try Automix free. You upload your stems, mix, and preview without spending anything, and your first download is free.

Building a product? Developers can embed RoEx mixing and mastering with the Tonn API.