CC recommends: Popular music

Dave Rawlings Machine, A Friend of a Friend. Gillian Welch and her longtime sideman switch places for a loose, mostly acoustic record, with help from members of Old Crow Medicine Show. As a guitarist, Rawlings is the rare formally schooled hotshot whose take on traditional country expands rather than suffocates it. He's also a pretty serious songwriter, from the breezy fun of "Sweet Tooth" to the eschatological edge of "I Hear Them All," co-written with Old Crow's Ketch Secor.

Carolina Chocolate Drops, Genuine Negro Jig. While this trio is more deeply steeped in old-time string band music than is Rawlings and company, it ventures even farther from it. The multi-instrumentalists met at a gathering of black banjo players and studied under Joe Thomp­son, a fiddler in the oft-overlooked Piedmont black string band tradition. Their new record ranges from traditional songs to originals to a cover of R&B singer Blu Cantrell, all performed energetically and expertly.

Howe Gelb and A Band of Gypsies, Alegrías. "Indie rock/flamenco crossover record" sounds like a silly gimmick. It isn't. Arizona songwriter Gelb's prodigious output—he has more than 40 albums, and two this year—features several such stylistic excursions, and here as usual he integrates disparate pieces into a strange but lovely whole. His brainy songs and raspy singing are supported by quietly grooving arrangements, with his Andalusian collaborators' fancy fretwork front and center.