I would highly recommend that you check out the documentary ”Pianomania” if you haven’t seen it already. It follows a Steinway piano tuner as he tunes instruments for a few famous pianists doing exactly the kind of thing you mentioned.
Relatedly, the book "Grand Obsession" tells the story of one pianist's truly obsessive search for a piano with a particular sound. I found it fascinating, moving, and a little terrifying.
kwindla|3 years ago
https://www.simonandschuster.com/books/Grand-Obsession/Perri...