When the "Reggae Sunsplash" tour pulls into the Merriweather Post Pavilion tonight, the musical revue will be divided between older acts (Burning Spear and Freddie McGregor) who emphasize reggae's distinctively Jamaican roots and younger acts (Shinehead, Shelly Thunder and Marcia Griffiths) who incorporate North American hip-hop trends into reggae. The contrasts should get people asking, "At what point does this music stop being reggae and become international pop with a reggae flavor?" and "Does it really matter?"

Burning Spear: 'Mek We Dweet'

There's no question about Winston Rodney's reggae authenticity: Under the stage name of Burning Spear, Rodney has been recording singles with heavy doses of the island's trademark syncopation and Rastafarian philosophy since the dawn of reggae in 1969. His new album, "Mek We Dweet" (Mango), features the Burning Band (with the Burning Brass), one of the few top-notch reggae bands since Bob Marley's Wailers to sustain a long-term relationship with one singer. Lenford Richards is playing more rock-and-roll guitar breaks these days, but the core of the band's sound is still the loping rhythm that lends a hypnotic quality to Rodney's gravelly chanting/singing.

Like its predecessors, the new album repeatedly refers to Rodney's hero, Marcus Garvey, and Garvey's vision of reuniting the African diaspora. Rodney is not as melodic or as inventive as contemporaries like Marley, Bunny Wailer, Jimmy Cliff, Joseph Hill and Toots Hibbert, but the Burning Spear albums represent Rastafarian music in its least diluted form. It's a tradition that has inspired countless musicians, and as long as Rodney keeps it breathing and vital, he provides an invaluable service.

Shinehead: 'The Real Rock'

One of last year's best albums in any genre was Sly & Robbie's "Silent Assassins," which united North American rapping with the Jamaican toasting that first inspired it. One of the hottest young stars in this rapping/toasting fusion field is Shinehead, born in London, raised in Jamaica and now residing in New York. Shinehead stands out in the crowd because he can actually sing as well as rap with authority, and he shifts from soul singing to Jamaican patois to hard-edged Bronx street talk to hilarious comedy routines without a hitch on his third album, "The Real Rock" (Elektra).

Shinehead shines as a legitimate singer on the bouncy reggae tune "Dance Down the Road" and on the Smokey Robinson-like love song "Till I Kissed You." He displays a Jazzy Jeff-like wit on one song that starts out like an anti-drug diatribe but turns into a description of the addictive qualities of Nintendo. He breaks with rap's prevailing macho ethic by praising "Love and Marriage" on a Jamaican toast set atop a dub version of the old Frank Sinatra standard. The album's highlight, though, is an inspired remake of Sly Stone's "Family Affair," which mixes slap bass, scratching, soul singing and speed-rapping into an imaginative defense of black music, black neighborhoods and the black family.

Andrew Tosh:

'Make Place for the Youth'

Shinehead is an exceptionally talented young man, but his music can't be accurately described as reggae. If Jamaica is to avoid becoming one more outpost of international pop, young musicians must carry forward the distinctive reggae tradition. No one's doing that better than Andrew Tosh, the son of legendary Jamaican singer Peter Tosh. The young Tosh's second album, "Make Place for the Youth" (Tomato), displays his late father's deep, authoritative voice and musical originality but not his preachiness. George "Fully" Fullwood, the bassist in Peter Tosh's last band, is the bandleader, producer and co-writer on Andy Tosh's new album, and Fullwood creates a melodic, funky, fresh version of the classic reggae sound.

The album's first song, "Stop What You Doin'," is Tosh's plea to end comparisons between himself and Ziggy Marley (the son of another late reggae legend), but one can't help but note that his vocals and production are every bit the equal of Ziggy's, and his songwriting is decidedly better -- its quality is obvious on the coming-of-age confessions of "Things I Used to Do," the philosophical metaphors of "Time Is Longer Than Rope" and especially "Why Did You Do It," the intensely personal and angry response to his father's murder.

Reggae Reissues

Bob Marley & the Wailers' 13 albums for Island Records, the most treasured catalogue in reggae history, has finally been released on compact disc -- an event analogous to the release of the Beatles' CDs in the rock world. The digitally remastered CDs have brought a new clarity to these classic recordings, opening them up and allowing the listener to pick out bass and guitar lines as never before. They've been released on the Tuff Gong label, the Wailers' original record company in Kingston, and "Could You Be Loved" from the "Uprising" album has been newly released as a single. All 13 albums are worth owning, but the best are the early ones -- "Natty Dread," "Catch a Fire" and "Burnin' " -- and the greatest reggae album ever made, "Bob Marley & the Wailers Live!"

Another seminal reggae group, the Itals, has also just had its back catalogue reissued on compact disc by Nighthawk Records (Box 15856, St. Louis, Mo. 63114). The Itals' David Isaacs and Ronnie Davis sing sweet, full harmonies behind the trio's fine lead vocalist, Keith Porter, in an exemplary fusion of Jamaican gospel singing and reggae's rural branch (ital means "natural"). The Itals' fine records have been hard to find on vinyl, but now the trio's mesmerizing harmony singing and austere arrangements can be heard on four CDs: the 14 singles collected on "Early Recordings 1971-79"; the 1982 U.S. breakthrough album, "Brutal Out Deh"; the 1984 collaboration with the Jah Children, "Give Me Power"; and last year's collaboration with the fine Roots Radics band, "Cool and Dread."