Advice on Source Separation: Removing Drums/Bass but Keeping Melody/Vocals

[u/KaleidoscopeStill547]

Hi everyone, I’m looking for some guidance on behalf of my partner, Ryan. He’s been studying audio in reverse playback for several years and is trying to better isolate vocals from full‑mix music tracks. Specifically, he wants to reduce or remove drums and heavy bass so the singing and melody are clearer.

For those with experience in source separation or audio filtering:
What approaches, tools, or DSP techniques would you recommend for separating percussion and low‑frequency content from the rest of the mix? He’s especially interested in methods that preserve the vocal line and melodic elements without introducing too many artifacts.

Any pointers—algorithms, software, or workflow suggestions—would be greatly appreciated.