Split stems on your own machine: a Demucs guide, and why unreleased tracks should stay off web uploaders
Demucs, the open-source separation model that came out of Meta's research lab, still runs well on an ordinary laptop. Here is how to install it from the maintained fork, what the quality trade-offs are, and why a demo or a client's session is better split at home than on a free website.
AIvia Meta / GitHub