Demucs is a Music Source Separation tool for extracting 4 stems - Drums, Bass, Vocals, Synths. It's by far the best one I've heard.
You can find the GitHub project here - https://github.com/facebookresearch/demucs
We will be installing it in the cloud, using Google Colab, and processing tracks with the default model that it comes with. You can also read how to train it with your own dataset.
STEPS:
1. Download this archive and upload the folder "Demucs" to your Google Drive.
https://mega.nz/file/ZHxjGBjJ#NUuH7k...MjEfb_fViSweVI
2. Go to https://colab.research.google.com/ and click on "Upload".
3. Download this file and upload it to Google Colab.
https://mega.nz/file/wH5n3TQI#Zk79MI...qOz8vXC0e7_CUE
4. Play all the steps in a row, waiting for each one of them to finish first.
Disclaimer: The second step sometimes could take very long time to finish. Some time it will be 2 minutes, other times - 15 minutes. I can't fix that.
5. When you get to the fourth step, click on the orange/pink text and only edit the name of the song with your chosen one.
Make sure the extension (.flac/.wav/.mp3 etc.) is correct. The song should be found straight in your Google Drive.
First, it will download the pre-trained model, which takes about 4-5 minutes, and after that, it will split your song which takes roughly the same time, if not quicker.
6. After you've played the last step (exporting your stems to your Google Drive), you should find your audio files in a new folder "separated" >> "demucs_extra".
Disclaimer 2: Most of the time, it picks up background vocals as synths, though not all of them. This is a known downside.