The Blasters find themselves caught between two different rock 'n' roll goals: their desire to celebrate the roots of American music and their desire to reach as broad an audience as possible. In a market where the latest studio gimmick or catchy jingle carries more clout than tradition, these goals often end up as contradictions.

The Blasters' new album, "Hard Line" (Slash/Warner Bros. 9 25093-1), tries to reconcile such contradictions. Accordingly, the band has subtracted its horn, beefed up its guitars and hired outside producers for the first time to put it all in focus. Most importantly, Dave Alvin's songwriting has grown dramatically -- the melodies are finally as prominent as the rhythms, and the lyrics tell the hand-me-down stories of the best folk songs.

"Trouble Bound" demonstrates how deeply rooted music can be appealingly presented to a mass audience. Alvin reaches into the rockabilly past for the always relevant theme of a good-time Saturday night and builds the song around an old-fashioned, twitching guitar riff. Producer Jeff Eyrich mikes Bill Bateman's drums to make the dance beat jump out. One of Alvin's more memorable melodies is reinforced by harmony vocals from the Jordanaires, Elvis Presley's old singers. The song should satisfy both record collectors and video dance club devotees.

John Cougar Mellencamp, who enjoys a broad audience, wrote and produced one cut for the album, "Colored Lights." Mellencamp, a longtime admirer of the Blasters, uses his strong pop instincts to provide the group with the radio hook it's never had. Singer Phil Alvin (Dave's brother) belts it out, and the band gives the song a distinctive Blasters syncopation.

Mellencamp's producer, Don Gehman, produced "Just Another Sunday," which Dave Alvin wrote with John Doe of X. Gehman manages to make the bleak tale of a broken-hearted lover watching TV preachers in an out-of-town motel sound like a Rolling Stones single. The lyrics are a model of economy -- drawing a powerful portrait of depression in two simple verses. Alvin does the same thing on the hard-rocking "Dark Night" by implying far more than he states in the story of violent racial conflict in a changing neighborhood. His ominous blues guitar reinforces the mood.

Much of the album has the same Louisiana swamp-pop sound that another California songwriter, John Fogerty, has drawn on. "Hey, Girl," with an accordion solo by Los Lobos' David Hidalgo, and "Little Honey," with a fiddle solo by Richard Greene, both sound Cajun with deceptively simple, folkish lyrics. "Help You Dream," a bar flirting song, has a witty New Orleans R&B feel with scat singing by the Jordanaires. Most of the rockers have the "chooglin' " sound of Fogerty's best records with Creedence Clearwater Revival.

The Blasters' "Hard Line" ends with two brilliant rockers by Alvin. "Common Man" is a savage indictment of a limousine politician who uses jokes, the Bible and Abe Lincoln quotes to charm the people even as children go hungry, miners are forced to strike and minorities get shot. The prodding guitar and thrashing rhythm section are every bit as savage as the lyrics.

"Rock and Roll Will Stand" is about the most common kind of rock 'n' roll musician -- the one who "almost had a hit." Tantalized by the elusive promise of stardom, the song's character goes from a cover bar band to a record contract and back to a day job. As he gives up the hunt, a younger kid is setting out on the same road, and the song concludes that even though individual musicians fall by the wayside, rock 'n' roll itself goes on. Gene Taylor's boogie-woogie piano and John Bazz's galloping bass testify to the vitality present even in such failure.

Despite critical raves and a cult following, the Blasters face the possibility of becoming like the character in that song. Even though they represent one of the best traditions of American music, they know enough rock 'n' roll history to realize that their significance is limited until they can bring that music to a wide audience. This album is a conscious, honorable attempt to do just that.

Much as the Blasters have joined the blue-collar ranks of Bob Seger and Bruce Springsteen by recasting rock roots and political themes in mainstream terms, Guadalcanal Diary has joined the North Georgia ranks of R.E.M. and the Swimming Pool Q's in a modern updating of literary folk-rock.

Gaudalcanal Diary's first full-length album, "Walking in the Shadow of the Big Man" (DB 73), weds the thick atmospherics of R.E.M. producer Don Dixon to the surrealist fables of songwriter-guitarists Murray Atwell and Jeff Walls.

Atwell and Walls sometimes get ponderous, but they have a knack for intriguing phrases and quirky little melodies, and Dixon turns the best of them into ringing folk-rock anthems. Highlights include the pagan spiritual "Why Do the Heathen Rage?"; the twisted love song "Pillow Talk"; the anti-imperialist rock march "Trail of Tears"; and a fast live version of the old folk standard "Kumbayah." The band performs tonight at the Anti-Club (1850 Connecticut Ave. NW).