The District-born group Experience Unlimited in the 1970s. (Vinyl MePlease)

Are you older than old-school? Then maybe you knew Experience Unlimited a decade before they had the world doing “Da Butt” in 1988 — way back when the legendary D.C. troupe was still playing a mix of breezy funkadelia and primordial go-go. Four decades later, new-schoolers have a chance to get fluent. The band’s 1977 debut vinyl platter, “Free Yourself,” is finally back in circulation thanks to Vinyl Me, Please, a popular subscription service that operates in a record-of-the-month style.

Of course, the label responsible for first putting “Free Yourself” in rotation was Black Fire, an imprint founded by Jimmy Gray, a District-raised DJ and impresario who built his operation on a strong aesthetic (progressive ­Afrocentrism) and an enduring business model (an artist-friendly 50/50 profit split adopted by countless indie labels that followed). In addition to Experience Unlimited’s auspicious debut, Black Fire also minted fantastic recordings by the Virginia soul-jazz group Oneness of Juju — a few of which Vinyl Me, Please is also reintroducing to the world.

To celebrate, swing by an unofficial, unorthodox release party taking place Sunday evening featuring the Nag Champa Art Ensemble, a genre-melting group that’s carrying the spirit of Black Fire into the 21st century. These guys are heirs to the Black Fire ethos, quite literally. Nag Champa bandleader Jamal Gray is Jimmy Gray’s son — and he’ll have records at the merch table.

Show: Nag Champa Art Ensemble performs Sunday at 4 p.m. at the Eaton Hotel, 1201 K Street NW. Free.