I often have voice recordings with a lot of background noise (e.g. a public lecture in a room with poor acoustics, recorded from a phone in the audience — there's usually sounds of paper rustling, noises from the street, etc). Is this "source-separation" the sort of thing that could help, or does anyone have other tips? The best thing I have so far is based on this https://wiki.audacityteam.org/wiki/Sanitizing_speech…
https://www.izotope.com/en/products/rx/features/dialogue-iso...
Cheaper versions of RX still have various noise reduction tools, de-verb for reducing reverb and room echo, and a range of spectral editing tools as well.