u/gabrielelosurdo

TL;DR: I made a free Mac app that saves rekordbox's stems, so tracks you've already separated load about 4 times faster. It can also swap rekordbox's stems model for Demucs v4, a newer version of the model rekordbox's own is based on.

Download and details: https://github.com/Gabe-LS/rbstemsplus

I've only been using rekordbox for about five days, but I wasn't sold on how it handles stems from the start. The separation isn't always great, and rekordbox re-separates the same track every single time you load it (eating CPU, memory and battery). Then I started reading around and found loads of threads and YouTube videos saying pretty much the same thing.

So I spent most of those days (with a lot of help from AI) building RB Stems Plus. It does two things:

Demucs v4 swaps rekordbox's separation model for a newer one. rekordbox uses Demucs v3, an older model from Meta that Pioneer lightly retuned. Demucs v4 is Meta's newer version, converted so rekordbox can run it.

Does it sound better? It depends on the music, and on the stem. Where I had a track's real stems, I measured which model's stems came closer to them:

• Pop and rock: on MUSDB18, the usual test set (50 songs with their real stems), Demucs v4 was closer on every stem.
• Electronic: on six tracks with their producers' stems, Demucs v4 was closer on drums and bass, rekordbox's model on vocals and the rest of the music.
• Rumble techno (no real stems here, so by ear): on Lunfardo by Ignez, rekordbox's model kept a short low hit in the bass stem, while Demucs v4 put it in the drums. To my ears, rekordbox's split was closer there. Other models I tried (htdemucs_ft, mdx_extra, SCNet, BS-RoFormer, AudioShake, Ableton's stem separation) each split it in yet another way.

So try it on your own tracks and keep whichever you like: you can switch back to rekordbox's model any time.

The catch: Demucs v4 is slower. It separates a track at about 5 times playback speed, compared with about 15 times for rekordbox's model. That's where Stems Cache comes in.

Stems Cache is probably the part I like most. It saves the stems rekordbox makes, with either model. The next time you load a track you've already separated, its stems are back in about 7 seconds and the model doesn't run at all, so there's no extra CPU or memory load.

I timed Lunfardo (6:27) in rekordbox: 26 seconds with rekordbox's model, every time you load it; 77 seconds the first time with Demucs v4; then 7 seconds from the cache.

https://preview.redd.it/hoezkwfivsuh1.png?width=1600&format=png&auto=webp&s=117571bebd78b9143a4fcda7bc4e02200bcee893

A few details:

• Mac only, for now. I've tested it on macOS 26 with rekordbox 7.2.18 and 7.2.19.
• You need STEMS already working in your rekordbox (it depends on your rekordbox plan).
• The two features are independent: install one or both.
• Stems Cache needs an admin account, and macOS asks you to allow it the first time.
• Free and open source (MIT).
• It doesn't touch your music or your rekordbox library.
• No tracking: nothing about you, your music or your library leaves your Mac.
• Uninstalling puts rekordbox back exactly as it was.
• Not affiliated with AlphaTheta / Pioneer DJ in any way.

This is an early version that I built around my own needs, so I'm very open to tweaks and feature requests. If something doesn't work on your setup, open an issue (the app can make a report for you) and I'll take a look.

A couple of days ago, I attended the Outloud Festival 2026 in Turin, Italy. I’d been waiting for it all summer because I’d had a couple of rough months and really needed to decompress.

Unfortunately, things didn’t go the way I, or many others, expected, and I came home the next morning with a bitter taste in my mouth (no, no, not the one you’re thinking of).

First, very little information was shared in the days and hours leading up to the festival: zero emails, no detailed timetable published anywhere, no map of the venue, and no replies to social media messages. The only real info post appeared just a few hours before the event opened and, among other basic details, clarified something that had never been mentioned before: re-entry was not allowed. Many people complained, especially since the festival was supposed to last 16 hours. Some asked for an explanation, but no one from the organization replied. Twenty-four hours later, they deleted the post.

Since leaving the venue and coming back in was impossible, I changed my plans and arrived at around 8 pm. As soon as I passed through the entrance gates, I finally saw the timetable and… Surprise! DVS1’s set had just ended. Ok, I thought. Let’s not start off on the wrong foot. Forget about it. I went to the toilet, found it in a pretty dramatic state (“forget about it,” I told myself again), and finally lost myself in Helena Hauff’s wonderful set.

There was plenty of space to dance, a convenient web app for paying at the bar, and a nice crowd all around. Extremely chatty, though, as Italians at festivals always are. I really enjoyed the next three hours, meeting the great people behind the Neutravel project (https://www.instagram.com/progetto\_neutravel) and catching an unbelievable set by Jeff Mills.

Then, after midnight, as if in some dark fairy tale, chaos arrived.

All the outdoor areas either closed down or had their volume turned down to lounge-bar levels, leaving thousands of people with no option but to patiently queue, sometimes for up to an hour, outside the entrances to the two relatively small indoor spaces where music was still being played at club volume.

Once you finally got in, just as you were about to celebrate… Surprise! The room I’d chosen had no bar and no other way to get a drink, including water. Every other person seemed to be smoking, the temperature was tropical, and airflow was nonexistent. Thirty minutes later, I left in search of water and a toilet.

One bottle of water: €3. “Is there a fountain?” I asked. “No.” Except there was one. Just 30 meters away from the very same bar where I’d been told there wasn’t. Others had found it before me, and there was a constant pilgrimage of thirsty people refilling their bottles. Just to test the situation, I went to the three other bars and asked the same question. I got the same answer every time: “There is no fountain. Sorry.” Oh, one thing worth noting: the €3 bottled water was at room temperature.

After using the toilet, which was completely unmonitored and had become a biohazard scene 12 hours into the event, I tried to enter the second indoor area. There was no queue anymore. At around 2 am, the security staff (shout-out to them for their patience and professionalism, given the situation) stopped regulating entry. That made getting in quick, but the crowd situation inside was a little overwhelming. Again: too many people, smoke, heat, very little air. For the first time in my life, I went dancing next to an emergency exit. You can understand why, right?

At 3 am, after a lot of people had left, the situation returned to something close to normal. Of course, you were dancing on piles of cigarette butts, plastic bottles, and cups. Of course, every trip to the toilet required a quick prayer. But all in all, especially compared with the previous three hours, I really enjoyed myself for another hour before leaving at 4 am.

The day after the event, the organizers published a post-event carousel on Instagram and Facebook. Dozens of people complained. Twelve hours later, they removed the post. Another twelve hours later, they posted a story apologizing for the issues many people had faced.

It was only the second edition, and I understand that organizing an event like this in a venue that wasn’t designed to accommodate that many people is anything but easy. So I do thank the organizers for the effort they put into it and for giving many people the chance to enjoy themselves for several hours.

That said, I have to admit that I will return to Outloud only if I see a significant change in their approach.