God this takes me back...
For most of 1979, I was part of a showband called "The Hipnotics," who were touring the Chitlin' Circuit of Massachusetts (yes, in those forced-busing days, there was one)...
Whenever our first show set ended, the DJ in the booth would put this, and stuff like it, on the system for dancing.
While the above-ground clubs were listening to "Fly Robin Fly," "More More More," and "Disco Lucy," the clubs in the Chitlin' Underground were playing great stuff like this:
Pure Groove.