Lonesome River Band and Special Consensus are celebrating 30 and 37 years respectively as working bluegrass bands. Both have excellent reputations, and both integrate traditional and modern sounds in ways that have pleased traditionalists and modernists in the genre's fervent, if not exactly mass, audience.

Naturally, neither of these outfits has the same lineup it had when it started out. Every one of LRB's original members has departed. Banjoist Sammy Shelor, who joined up in 1991, is now the oldest presence in the ranks. Special Consensus -- once the Special Consensus Bluegrass Band -- still houses its founder, banjo man Greg Cahill, while the other members are new or relatively so. Guests in for the occasion, however, include two alumni, Chris Jones and Josh Williams, who today lead their own groups.

Though both celebrate happy longevity, each of these CDs has its own way of marking the occasion. Chronology, the first of three promised retrospectives (presumably of the same abbreviated length; there are eight cuts), revives songs from the band's early days in the 1980s and redoes them in the style of the current LRB. Since I can't claim to have heard everything, much as I would like to, I confess that my exposure to the originals is at its best hit and miss. All I can do is attest to how pleasingly each song emerges in this iteration. The LRB's well-known strengths are here: propulsive rhythm guitar and percussive mandolin, not to mention sterling harmonies and impeccable material.

The disc kicks off with a sharp-edged reading of Eric Andersen's "Close the Door Lightly When You Go," one of the small number of '60s folk-era songs to wander into the bluegrass repertoire. I suspect LRB got it from the Dillards's long-ago cover rather than from Andersen's early Vanguard album. (Not to quibble, but the composer credits misspell Andersen's last name.) Other songs and tunes hail from bluegrass, country and traditional sources. The album closes with a spirited, unexpectedly moving reading of the venerable fiddle tune "Angeline the Baker" (from Stephen Foster's 1850 song "Angelina Baker").

Unless the material is all original, I seldom hear a bluegrass album with as little material familiar to me as Special Consensus offers up in Scratch Gravel Road, which features only two within-the-band compositions. The rest depend upon outside writers, a consideration that helps give this veteran band a fresh sound yet still infused with traditional themes and neo-traditional picking and harmony. Craig Market's "Monroe" conjures up the imperious, no-nonsense personality of bluegrass founder Bill Monroe, highlighting Monroe's expression of dismissal when affronted by music that failed to measure up to his exacting standards: "That ain't no part of nothin'."

If there are inferior cuts, or anything close, they got past me. Still, to my taste the standouts are the band's rousing arrangement of the country-pop standard "Sea of Heartbreak" (a tricky song to do bluegrass style), the melancholy lament "My Memories of You," and Tim Stafford's "Shoulda Took a Train." Then again, the unaccompanied gospel-quartet arrangement of "On My Way to the Kingdom Land," from the 1930s repertoire of the Golden Gate Jubilee Quartet, and the barn-burning opener "Old New Straitsville Moonshine Run" will draw no complaints from this quarter.