If there is a definition of "roots-rock," it's not rockabilly so much as 1960s guitar-rock, these days -- Bruce Springsteen and a handful of others fading into career twilight notwithstanding -- out of fashion in a post-rock pop scene. Sometimes what survives of the mainstream, guitar-centered rock of decades ago masquerades as blues-rock as if to cover it in a vernacular authenticity marked by the occasional blues chord.

The Nighthawks, who have been around since the 1970s, play roadhouse music with the authority of guys who have done it for a long time. They still record fairly prolifically, usually stressing the blues side of their collective personality. As enjoyable as anything they've released in recent years, All You Gotta Do highlights mid-century blues sounds (Willie Dixon, Sonny Boy Williamson II, R.L. Burnside) along with obscure but worthy covers from the likes of Larry Campbell ("When I Go Away," the lyrics written around a phrase associated with Woody Guthrie), Randy Newman (a slide- and harmonica-driven, borderline-eerie reworking of "Let's Burn Down the Cornfield") and Jesse Winchester. The arrangement of Winchester's "Isn't That So," always a favorite of mine, from the late singer-songwriter evokes not the folk-pop of the original but The Band.

The vocals are appropriately gruff and world-weary as benefits the jaded outlook of four been-everywhere-seen-it-all musicians schooled in ragged edges, hard knocks, and the rhythms that propelled the songs that soothed listeners and dancers in liquor-soaked dives. By now first-generation electric blues is pretty much a form of traditional music, and roots-rock is heading that way. Which means with each passing year the Nighthawks, whatever their personal feelings about being so identified, are closer to acting as preservationists. When you preserve as eloquently as they do, that's an honorable calling. All You Gotta Do is their most richly realized album in a decade.

Delta Wires are a seven-man blues band from the Bay Area, best known on the West Coast and new to my inland ears. Born in Oakland attests to their immersion in r&b, jump blues and jazz; the "Delta" in the title isn't much in evidence on the current disc. The group sound is heavily horn-oriented, owing to the chosen instruments of three members (saxophones, trombone, trumpet). Band leader and harmonica player Ernie Pinata handles the lead vocals, singing mostly originals in a smooth, swing tenor.

Though my personal taste tends toward more rough-cut approaches to blues, there is no question that Born makes for pleasurable listening and engenders an appreciation for the Wires' thoroughgoing professionalism. At the same time, good as this recording is on its own terms, one suspects that one is getting only a paler representation of what they must sound like in their natural habitat, which is live performance.