When Stem Creator will be upgraded? Bitrate of the stem file is 256kpbs max since 7years

This has been a struggle since the beggining of Stems and the issue is NI doesn't do much about it.

Interestingly enough as a Mac user I now have to make the Stem files using ALAC but on a windows machine, and then play it on my Mac because the stem creator tool isn't working on a updated Mac.

I do not think that there is anything happening related to stems anymore. In maybe 3 - 4 month with the release of real time AI Stems in Traktor Pro 4, Stems based on tracks will not be a topic anymore for NI.

I see this sad since for DJ's / Producer creating there own Stemps this will not be a good replacement.

Does Demucs or any other program make Traktor STEMs from stem files that user provides? And not using ALAC so that it may be ysed on Win....

I have had a look into the Stem SDK contained in the ZIP file downloaded from the Stem website.

In it you can find a script which you can run in a terminal. Terminal, if you don't know, is a text-based way to run programs, without graphical User Interface.

The good news here is that the script is based on 2 wide-spread (despite outdated) software components:

• AVCONV (better replaced by FFMPEG, the ultimate way to convert and put into containers audio and video data)
• Python 2.7 (now replaced by Python 3)

Both of them are free software (thank you open source).

Python is only necessary to handle the complexity of the Stem creation:

• format specification,
• reading of a parameter file (in the JSON format),
• file format conversion if not in supported formats,
• error if target file format not supported, etc.

I have analyzed the script and it only calls the AVCONV utility program to convert the audio files to AAC most of the time, with the 256k bitrate (which you already know).

If you want to make a test, provided you have the mixed file and 4 separated tracks, and are familiar with the FFMPEG program and the terminal (or ask a geek 😜), you can run the following command in your terminal (you can guess what was the file I used for the test):

ffmpeg -i Daft\ Punk\ -\ Something\ About\ Us.flac -i drums.flac -i bass.flac -i bass.flac -i other.flac -i vocals.flac -c:a aac -map 0:0 -map 1 -map 2 -map 3 -map 4 Daft\ Punk\ -\ Something\ About\ Us.stem.mp4

Explanation:

• ffmpeg is the magical program with merges all audio files together
• every input file must be preceded with the -i parameter
• there are 5 files (therefore 5 -i sections): the "mixed"/final track, and 4 separated tracks
• if the file names contain spaces, make sure they are "escaped" with the \ character -- or just remove/replace them in every file name before the operation
• -c:a aac means ffmpeg will convert them into the AAC codec
• the -map parameters ensure the tracks are not merged but are kept separated in the target file
• the last part, after the -map parameters, is the target file name which will be produced at the end of the process. Here again, same instructions than above if the file name contains spaces

DIY! It is easy and hopefully it will work.

I did that on Linux, because my MacOS is outdated and my MacBook Air is 11 years old, so I only open it to run Traktor and Ableton.

To overcome the sound quality issue, you can try to add a parameter in the ffmpeg command to force a high bitrate conversion. Just add -b:a 512K right after the -c:a aac section to have a 512kbps bitrate instead of the 256k one.

Since the Stem file is only a container of 5 audio files, and since Traktor is compatible with the FLAC codec, we could expect that we could encode the audio data in the FLAC format instead of the AAC one inside the container. However the Traktor Pro software can handle individual FLAC files, but could possibly not support a container of them.

If you want to try to generate Stem files with FLAC encoded files, just replace the -c:a aac part with the -c:a flac string (don't add a bitrate parameter here).

For the brave ones, please try to generate such files and tell us if the Traktor software can play them. And let me know if you need more assistance in these operations.

Cheers!

Valentin