The best funk band: early Earth, Wind and Fire (before 1976 when they lost themselves into disco). Their funk was harmonically rich and rhythmically complex: A blend of jazz, soul, funk and R&B. Listen to their live double record Gratitude (1975).
Also some demo’s by Prince are amazing.
Not sure, but the rawness just breathes life and blows most studio stuff out of the water.
[Edit] bonus end game track: https://youtu.be/dQN3fxoIOpk (thank you Gilles Peterson)
The real thing: https://www.youtube.com/watch?v=9pA2tXOjDto&list=PLxh03o1BpV...