Even though it's not DIY or pure analog, you might want to check this module out anyway. I just got one and it seems a perfect fit for the styles you mentioned.
https://www.modulargrid.net/e/4ms-company-spectral-multiband-resonant-filter
-- Synnic
Oh lord, yes. I got to play with one at Modular Eight in Portland when I was there. Unfortunately waaay out of my price range (advanced hobbyist).