About NUO-STEMS
A journey from passion to innovation, crafted by a DJ for DJs.
Meet the Creator
Hi, I'm Alex — but you might know me as DJ NUO. I'm a developer, creator, and passionate DJ from Ukraine🇺🇦 who found myself facing a problem that many of us in the DJ community share.
Like many DJs, in 2020 (!) I wanted to play with STEMS in Traktor Pro — to isolate vocals, drop the drums, filter the bass, and create those magical moments on the dancefloor. But the tools available weren't quite there yet. Traktor Pro was the only software that supported STEMS, but you couldn't split STEMS using AI — you had to use NI Stem Creator and it only worked if you had original stems from the artist.
So I did what any developer would do: I built my own solution. What started as a personal project to solve my own needs has grown into something much bigger — a tool that thousands of DJs around the world now rely on.
How It Started
In June 2020, I released the very first version of NUO-STEMS — version 1.0.0. It was simple, used Deezer Spleeter algorithm, and it worked. It could process multiple tracks at once, convert them to the .stem.m4a format that Traktor Pro understands, and preserve all the metadata including artwork. Most importantly, it worked on both Mac and Windows.
I shared it on Patreon, not knowing if anyone else would find it useful. But the response was immediate and overwhelming. DJs were excited. They were converting their entire libraries, sharing tips, and pushing me to make it better.
The Evolution
Version 2.0 — October 2022
This was a game-changer. I integrated Facebook Demucs v3, which delivered 10x better quality of separation (subjectively speaking). Yes, it took longer to process, but the results were incredible. DJs could finally get studio-quality STEMS.
I also added STEMS color customization, which was especially useful for Traktor S4 mk3 users with color pads.
Version 3.0 — March 2023
This release was massive. I completely rebuilt the UI from scratch with a modern tech stack. But more importantly, I added GPU acceleration support for both Mac and Windows. Now DJs with powerful graphics cards could process tracks in a fraction of the time.
I integrated Demucs v4 algorithms, which provided even better quality, especially for vocals. The new queue system made batch processing a breeze, and I added features like automatic collection.nml detection and highly accurate metadata transfer that eliminated the dreaded "drift" issue.
Version 3.1 — October 2024
This release was all about quality. I introduced a brand new algorithm called mel_band_roformer — also known as "insane" — which delivered insane quality of vocals, improving from 8.34 to 10.85 SDR score. The vocal separation was so good that DJs could finally isolate vocals with studio-quality precision.
But the improvements didn't stop there. Using the SDR (Signal-to-Distortion Ratio) metric, drums improved from 11.26 to 11.66, bass improved from 12.04 to 12.37 with minimal drums leaks, and the "other" stem improved from 5.75 to 6.92 with dramatically reduced drums leaks.
| Algorithm | SDR (Bass) | SDR (Drums) | SDR (Other) | SDR (Vocals) |
|---|---|---|---|---|
| htdemucs_ft (NUO-STEMS 3.0) | 12.04 | 11.26 | 5.75 | 8.34 |
| mel_band_roformer (NUO-STEMS 3.1) | 12.37 | 11.66 | 6.92 | 10.85 |
| Traktor Pro 4.0.0 | 11.51 | 10.60 | 5.43 | 8.07 |
I also added features like AI "sum of stems = original" for cleaning up stems and improved Traktor Utilities with better precision for transferring hotcues and beatgrids.
Version 4.0 — December 2025
The latest evolution. I pushed the STEMS separation quality even further, squeezing more power out of the existing algorithms and using new ones.
NUO-STEMS 4 comes with 2 new algorithms: mel_vocals_bs_others (Recommended) and bs_roformer. The mel_vocals_bs_others algorithm provides amazing quality, especially for vocals, while bs_roformer delivers great quality for all stems. Both algorithms significantly improve upon the previous generation.
| Algorithm | SDR (Bass) | SDR (Drums) | SDR (Other) | SDR (Instrumental) | SDR (Vocals) |
|---|---|---|---|---|---|
| mel_vocals_bs_others (NUO-STEMS 4 - Recommended) | 14.44 | 13.96 | 8.34 | 17.19 | 10.88 |
| bs_roformer (NUO-STEMS 4) | 14.44 | 13.87 | 8.54 | 17.45 | 11.14 |
| mel_band_roformer (NUO-STEMS 3.1) | 12.37 | 11.66 | 6.92 | 17.15 | 10.85 |
| Traktor Pro 4.0.0 | 11.51 | 10.60 | 5.43 | — | 8.07 |
With Traktor Pro 4's release, I saw an opportunity to create something truly special: natively linked STEMS. No more manual linking, no more hassle. Just seamless integration.
The Philosophy
Throughout this journey, one thing has remained constant: I built this for DJs, by a DJ. Every feature, every improvement, every decision comes from understanding what it's like to be behind the decks at 2 AM, trying to create that perfect moment.
The feedback from the community has been incredible. From the Facebook group to Discord to direct emails, DJs have shared their stories, their needs, and their excitement. That's what keeps me going — knowing that this tool is making a real difference in how people create and perform.
What's Next
The journey doesn't end here. I'm constantly experimenting, testing new algorithms, and pushing the boundaries of what's possible. Whether it's improving quality, increasing performance, or adding features you've requested, I'm always working on making NUO-STEMS better.
If you have ideas, feedback, or just want to say hello, I'd love to hear from you. Schedule a call, join the Discord community, or drop me an email. This is a conversation, not a monologue.
Join the Journey
Whether you're a seasoned DJ or just starting out, NUO-STEMS is here to help you unlock new creative possibilities. Experience the difference that comes from a tool built with passion, dedication, and a deep understanding of what DJs actually need.