How to clean stems in REAPER with Oxide

By Will Barratt, who builds Oxide · Updated 8 November 2026

Short answer: put each stem on its own track, add Oxide first in the track FX chain (or clean the file in the Oxide app and import it as a new take), listen to what was removed, then mix.

REAPER is a straightforward place to mix stems from Suno and other AI music tools. The usual snag is not REAPER itself. It is that the stems arrive harsh, thin, or a bit too shiny, and then every compressor and EQ you add makes that worse.

This guide is the REAPER workflow: import the stems, inspect them, clean the ones that need it with Oxide, then mix as you normally would. For what shimmer and artefacts actually are, see How to clean Suno stems. For plugin installation across DAWs, see How to set up Oxide in your DAW.

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Import the stems

Create a new REAPER project and set the sample rate to match the files (often 44.1 kHz or 48 kHz).
Drag each stem onto its own track, or use Insert and import the media files. Keep one part per track — vocal, drums, bass, and so on.
Line the files up at the same start point. Generated stems should already share a timeline; if one is early or late, nudge that item rather than stretching it.
Name the tracks clearly so you can solo the part you are inspecting.

If a stem sounds badly split, do not expect cleanup to finish the job. Listen in the gaps between phrases. Another instrument in those gaps is bleed from separation.

Inspect before you mix

Solo each track and listen in REAPER with the rest of the project muted.

Bleed: another part appearing in the gaps.
Residue: a glassy, metallic, or watery texture on the sound itself.

Play the original full mix alongside if you still have it. If the mix is fine and only the stem sounds damaged, the split is part of the problem.

Do not build a long FX chain on a shimmering stem first. Compression, saturation, and de-essing will often exaggerate the residue.

Clean a stem with Oxide

You can clean a file in Oxide (browser or the macOS/Windows app) and import the cleaned version back into REAPER, or use Oxide as a plugin on the track once it is installed.

Standalone or Web Studio

Open Oxide and load the stem.
Run a scan.
Listen to the cleaned stem and, if you can, to what was removed. You want shimmer and fizz, not the body of the part.
Export when it sounds right (WAV export is part of Pro), then carry on mixing.
In REAPER, replace the original item or put the cleaned file on a new take so you can A/B against the uncleaned stem.

Plugin on the track

Open the track FX chain in REAPER and add Oxide (VST3, AU, or CLAP, depending on your system).
Run the inspection on that stem.
Listen to what is being removed before you commit. If words or drum attacks appear in the removed signal, the pass is too strong.
Render or freeze the track when you are happy, so the rest of your mix chain is working on the cleaned sound.

Batch Triage in Lite checks up to 3 stems; batch folder render is part of Pro. Oxide Pro and Oxide Studio unlock 24-bit WAV export, the 5-band breakdown, and folder rendering.

Mix in REAPER after cleanup

Once the residue is under control, use REAPER as you normally would: EQ, de-essing, compression, sends, and a modest master chain. Compare cleaned and uncleaned takes at matched loudness.

If you are working through a folder of stems, clean the ones that actually bother you. Not every stem needs a pass.

Try Oxide Lite

Try Oxide on the REAPER stem that has been hardest to mix. Try Oxide Lite free. Pro unlocks everything.

Other DAWs: Ableton Live · Logic Pro · FL Studio · Cubase · Pro Tools

Common questions

Can I use Oxide inside REAPER?

Yes. You can clean a file in Oxide and import it, or add Oxide as track FX after you have installed the plugin.

Should I clean every stem?

No. Solo each one and clean the parts that sound harsh, thin, or metallic. Leave stems that already sit well.

Why do my REAPER compressors make Suno stems worse?

They are raising residue along with the useful sound. Inspect and clean first, then compress.

Which stems should I clean first?

Usually the vocal and the hats or cymbals. Bass and kick rarely need anything. Clean the parts that bother you and leave the rest.

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