This LP continues to be in heavy rotation at this listener's house:
Lou Donaldson - Cosmos (Blue Note, 1971)
George Butler produced this LP, but (aside from the voices) I think it sounds more like soul jazz that Bob Porter was producing for Prestige around that same time. The key sidemen on Cosmos are Porter regulars: Melvin Sparks, Leon Spencer, and Idris Muhammad. That (relatively) stripped-down, not over-produced "Bob Porter-like" soul jazz sound is one of the reasons I've been enjoying this LP so much.