ON A COOL, RAINY afternoon in Austin, Texas, Young Guru—Jay-Z’s personal sound engineer for the past 16 years—was giving a master class on recording and mixing techniques at Dub Academy, a music school and studio east of downtown. Lanky and lithe, the former high school basketball star radiated a quiet authority at the front of the room, befitting his nickname. While his disquisition ranged from best practices for setting sound levels to navigating life on the road, the audience—which included everyone from gee-whiz interns to producer Mannie Fresh, who mentored Lil Wayne—hung on his every word.

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