Jean-Marc Valin, who goes by the username jmvalin on Github and other places, has done a good amount of work involving speech processing, [noise-suppression], and [vocal-synthesis]. He also was the project lead for the [speex] codec which is optimized for voice as well as the [rnnoise] library.
Github: https://github.com/jmvalin
Website: https://jmvalin.ca/
Blog: https://jmvalin.dreamwidth.org/