Doo-wop’s mostly a cappella meld of melodramatic lead vocals and backing harmonic “oohs” and “ahs” can sound age-addled to those who weren’t teenagers as of the late ’50s. But don’t let this genre’s clichés keep you from enjoying its charms. This evening’s “Sounds of Doo Wop II” promises to deliver both the sappy and the sublime, with acts including the locally based Rainbows (who once featured Marvin Gaye) and the Legendary Orioles. The Orioles are an institution known for blending street-corner- and church-developed baritone, tenor, and falsetto voices in a way that’s mostly forgotten in contemporary music. Yet like the best modern twee-pop or quiet-storm soul bands, the doo-woppers’ approach timelessly captivates with memorable melodies and resonant tales of love and heartbreak. With Cleveland Stills and the Dubs, Five Discs, Capris, Memories, Velons, Winston’s Orchestra, and Avenue Grand Band at 7 p.m. at Show Place Arena, 14900 Pennsylvania Ave., Upper Marlboro. $20-$25. (202) 432-7328. (Steve Kiviat)