Kid Rock's "Rebel Soul," and Alicia Keys's "Girl on Fire" Jim Young/Reuters "Rebel Soul" by Kid Rock, above, and "Midnight Special" by Uncle Kracker hew to Nashville sensibilities. Of all the pop genres, country has manned its borders the most ferociously, and that's been to its detriment. A world with slow or no influx of new ideas is a dying one. But while you can police sounds, you can't police people, and the genre's embrace in recent years of the onetime rap-rock kingpin Kid Rock and his former sidekick Uncle Kracker has as much to do with their charm offensive as with their music. The front door wasn't an option for these two, who grew up in and around Detroit's hip-hop scene while harboring an appreciation for ragged Southern-style rock and country. Kid Rock has been reconciling these things for years, since he realized a straight-ahead rap career probably wasn't in the cards for him, even going so far as to record a sensitive, relatively spare album with the producer Rick Rubin - "Born Free" from 2010 - that was a bit of a rebuke to the up-all-night yowling that Kid Rock had made his breakthrough sound. "Rebel Soul" (Atlantic) is his first album since that one, and his ninth studio album over all, in a career that's moved from goofball hip-hop to sleazy rap-rock to, now, preservationist American heritage music. Who better, though, to catalog and celebrate this country's sonic lineage than someone who's consumed and regurgitated it all? "Rebel Soul" is Seger and Creedence and all the dirty "70s rock in between, with the lyrical clichés to prove it: "drugstore cowboys," check; "moonshine whiskey," check. The title track is plenty convincing Lynyrd Skynyrd manqué. The songs are designed for broad consumption - "Detroit, Michigan" is a roll call of places and their legacies that will work all tour long; "Cucci Galore" is a lost-night fantasia in which "Everybody wearing edible bikinis/Everybody want a chocolate martini." The most beautiful song on the album is called "Cocaine and Gin," naturally. Kid Rock is an amateurish singer, but over the last few years his unsteady squeal has been become burnished and is now credible, enough so that the one song here with gratuitous vocal processing, "The Mirror," feels like an insult to his mission. Kid Rock was famous before this, which means he had higher obstacles to traverse to achieve what he has. Uncle Kracker, by contrast, had almost a blank slate to work with, going from being Kid Rock's childhood friend to D.J. in his band to accompanying vocalist to solo singer to accidental soft-rock star. Or maybe not so accidental. Uncle Kracker has a clean, syrupy voice with a tiny bit of wheeze to it. At his best he approaches the banal charms of Jim Croce. Once on a major label, he's now on a smallish roots-music label, which seems like a misstep: "Midnight Special" (Sugar Hill) is easily one of the year's best country albums - though, in fairness, it's been a slow year - one that most bigger-budgeted stars would be grateful to have. It's produced by the veteran Keith Stegall, and it shows. "Midnight Special" is an almost totally guileless album, faithful to its smooth-rock and country-lite forefathers, and as polished as military shoes. Uncle Kracker sounds lovely and engaged on "Blue Skies" and "When I Close My Eyes." And "I'd Be There" features some striking, heartfelt songwriting: "If I could, I would crawl through the phone/Yeah, this drink gets me by but it don't get me home." The traditionalism of this album underscores the real reason Nashville has welcomed Kid Rock and Uncle Kracker with open arms: They're not invaders from the outside but prodigal children looking to come home. "Girl on Fire" (RCA) "Girl on Fire," Alicia Keys's fifth album, has two modes: lofty and submerged. Guess which one leads to better songs?