Remarkably, the 17 cuts of Epilogue: A Tribute to John Duffey and the 21 cuts of Always in Style, the 2000 Sugar Hill retrospective on Duffey's recorded output, manage not to overlap on a single song or tune. So if you have the latter in your album collection, don't be misled into thinking you can easily pass by the former, newer disc.

Duffey, who died of a heart attack in December 1996, started early, in July 1957 in a Washington, D.C., band that soon became known as the Country Gentlemen, among the most influential bluegrass ensembles in the genre's history. Anyone compiling a "best of" retrospective has much to draw from.

Duffey, the Gents' mandolin player, recorded steadily thereafter in a series of albums that caught the folk wave and in the process probably saved bluegrass from extinction. At the time bluegrass was a briefly popular style of mid-century country music on its way out of fashion. Meanwhile, the Gents seemed a radical, de-ruralized representation of this tradition-based genre, and indeed they were. One thinks of how bebop sounded to the jazz audience just a decade earlier, to some fans and critics no less than a rejection of the jazz tradition, only to be seen in time as an organic extension of that tradition. Today, the early Country Gentlemen's sound has affected so much of what came after it that it feels -- misleadingly -- like less a leap from past to future than it actually was.

A couple of years after leaving the Gents in 1969, Duffey participated in the creation of the Seldom Scene, which pushed bluegrass further in an urban direction. Duffey remained with that widely admired band, for all its personnel changes over the years, until his death. Duffey was notorious for his outsized stage personality, his habit of making outrageous jokes and hurling insults, often crude but usually funny, at hecklers. Seldom Scene guitarist Dudley Connell recounts cringe-inducing instances in the liner notes to Epilogue.

Most of all, though, Duffey is remembered as the "father of modern bluegrass," as some have called him, and as an innovative mandolin master (as well as a terrific tenor singer, though his picking skills have made that talent a footnote in the Duffey legend). As Jack Tottle put it in an early Bluegrass Unlimited profile, "In addition to his own impressive high-energy variations on Monroe-style mandolin playing, John did such unheard-of things as playing breaks on three or four strings simultaneously instead of the usual one or two. He twisted the strings, he played jazz chords, played breaks alternating between first and fourth strings, and sometimes he'd use fingerpicks instead of a flat pick." Yet he never sounded as if he were trying just to impress other mandolin players. His music was always moving and accessible to anyone open to creative melody-driven performance.

Bluegrass musicians Ronnie Freeland and Akira Otsuka got the idea for a Duffey tribute in the fall of 2002, then patiently rounded up singers and pickers over the next decade and a half. In short, Epilogue was a long time in the making. At least one of the guests, James King (who sings "Going to the Races," reworked by the late Carter Stanley from a traditional song), died well before its release this past June. Major figures on the current scene, vocalists and instrumentalists, show up to do honors, highlighting Duffey's wide-ranging, inspired taste in material from foundational artists like the Stanley Brothers, Bill Monroe and Flatt & Scruggs to traditional songs to neo-folk compositions by the likes of Bob Dylan and Tim Hardin. Out at the left end of the spectrum is an instrumental of Mary Poppins' "Chim-Chim-Cher-Ee," rendered by oldtime musician Bruce Molsky. It brings to mind Dr. Johnson's celebrated observation about dogs walking on their hind legs. It doesn't matter if it's done well, it's that it's done at all.

Though nearly everything belongs here, I like most of all Dudley Connell's reading of "He Was a Friend of Mine," for one thing because he sings it so affectingly and for another because he does the traditional version, not the usually heard Dylan rewrite first cut by Dave Van Ronk and spread everywhere from there. Speaking of Dylan, let me tip the cap to Steve Gulley's outstanding "Girl from the North Country," likely to remind anyone whose memory needs prompting of what a gem of a song this was and remains.

The Slocan Ramblers' Queen City Jubilee is getting reviewed alongside the Duffey tribute because (1) the albums have been getting extended airplay here in my office and (2) they demonstrate, coincidentally, the range of bluegrass. Well, sort of, anyway. Duffey liked the old music and did it well, if untraditionally. The Toronto-based Slocan Ramblers like the old music, too, except that they do it in the older way. By that I mean in a style that arguably could have predated Monroe's.

Actually, to be specific, they remind me of the late, West Virginia-born banjoist Don Stover, whose Things in Life (1972) occupies a special place in my heart. A nearly perfect amalgam of bluegrass and oldtime, it features songs that have remained vivid in my memory for decades (the title piece, "Old Reuben No. 1," "The Old Coon Dog" and others). One of those "others" is a Stover original, the condemned-prisoner's lament "Long Chain Charlie & Moundsville." The Slocans' Frank Evans sings it ably from an emotional vantage that echoes Stover's, in in other words with stoic reserve as death looms. Well, that, and Evans just sounds like Stover.

I don't know if the Slocans got "Mississippi Heavy Water Blues" (one of a number of songs inspired by the massive flood of 1927) from Doc & Merle Watson, whose arrangement feels something like one the Delmore Brothers could have brought to it, or from Barbecue Bob Hicks' 1927 country-blues original. They do, however, make it resoundingly convincing bluegrass. Other numbers -- e.g., "Hillbilly Blues/Deer on the River," "Riley the Furniture Man" -- are rarely clad in bluegrass garb, in good part no doubt owing to the sometimes startling ignorance of younger pickers toward the Southern folk repertoire from which bluegrass evolved, but the clothes fit splendidly. Evans's engaging "Mighty Hard Road," as its title suggests, could pass for a traditional number. On the other hand, the instrumental "Shut the Door" uses older sounds as the floor for what turns out to be relatively more modernist picking.

If there is no shortage of well-played bluegrass out there, some of it can sound a tad repetitive. Besides, a band labeled "traditional" is often only relatively so, and in comparison to what else is out there on the contemporary scene. In other words, only next to artists who are pulling the music more aggressively into the future, maybe even to a point at which next-generation "bluegrass" will be unrecognizable by any currently understood definition. The Slocans, who put their own sound atop the tried and true ones, keep bluegrass rooted and vital, at once recognizable and distinct. That's a special skill, and the Slocan Ramblers turn it into art.