Charles McReynolds was present at the creation. Not of the world, of course, but of a cultural explosion sometimes called "country music's Big Bang." In the mid-summer of 1927, producer Ralph Peer placed ads in newspapers encouraging Southern musicians to audition for recording contracts. Hundreds turned up in Bristol, Tennessee, to show off their stuff. A few -- the Carter Family, Jimmie Rodgers, Ernest Stoneman -- not only succeeded but went on to be famous.

In those days neither "Big Bang" nor "country music" (at least as currently understood) existed in anybody's vocabulary, though 1927 brought the first airing within physics of what would become the former. Meantime, commercial country music would be given a giant push forward. Even so, the music performed at Bristol (with the exception of Rodgers') is more like an early draft of bluegrass, a genre first preserved on wax two decades later, than the blue-collar fusion sounds that would be associated with Nashville's version of "country" in subsequent times. Bristol's celebration, represented on a variety of well-annotated CDs (if you're curious, the Country Music Foundation's two-disc, 35-cut The Bristol Sessions is a fine sampler), documents the Appalachian folk music of the 1920s. It has only the vaguest of links to what you'll hear, assuming you want to hear it at all, on your local country station.

While they did not become stars themselves, Charles McReynolds and the Bull Mountain Moonshiners would cut a couple of fiddle tunes, "Johnny Goodwin" and "Sweet Marie," on Aug. 1 before they faded back into the Virginia hills. McReynolds's grandson Jesse, however, would go on to join bluegrass's foundational generation as one half of the magnificent Jim & Jesse & the Virginia Boys. Jesse's innovative mandolin and his and brother Jim's vocal harmonies elevated them to royalty status, just a notch or two below Bill Monroe. The band toured and recorded till Jim's death early in the new century. Since then, Jesse has carried on alone.

Hard to believe that in the twilight of his career he would -- indeed, given how age decays the fingers and imaginations of even the most accomplished pickers, could -- put together an album as appealing as The Bull Mountain Moonshiners' Way. And astonishingly, it is not a bluegrass album. In its near-entirety it consists of traditional fiddle tunes played in the undiluted oldtime way. The material is taken from the Bull Mountain Moonshiners' repertoire as well as from the revered fiddler Marion Sumner when he played with the Virginia Boys in the 1950s.

Jesse McReynolds himself contributes mandolin, as expected, but surprisingly does a fair amount of the fiddling himself on nothing less than his grandfather's own physical instrument. A number of top-flight players (Michael Cleveland, Glen Duncan, Mike Snider, Raymond McClain and more) join him on assorted instruments out of the string-band tradition. If most of the tunes are familiar ones, they are done with such verve and nuance that if you don't steel yourself beforehand they may cause you to faint.

I am fortunate to have heard a lot of good oldtime music over the years, but this one is something special indeed. If it were a wax disc, I'd have spun it down to the grooves by now. Repeated listenings only enhance the pleasures to be had. If you love mountain music delivered straight from the heart and sent into the world wrapped in warmth and joy -- and oh yes, technical brilliance -- you miss this one at peril to your soul.

Mike Block's Walls of Time arises from another century, namely the current one, even though it reprises vocal numbers and instrumentals the McReynolds family and its contemporaries would have known, including the songs "The Blackest Crow" and "Wayfaring Stranger" alongside the tunes "Old Sledge" and "Forked Deer." But while traditional in origin, these are not traditional in Block's handling. As a classically trained cellist, he is far removed, geographically and temporally, from the realm in which the Old Southern Sound (Mike Seeger's phrase) came to be.

What sets this recording apart from the Jesse McReynolds disc is the mid-century folk revival, which opened up folk songs to original or even experimental interpretation. Either such interpretations work, or they don't. As the saying goes, the worst thing you can do to a folk song is not to sing it. Block is kind to the music in that way, and beyond that, he captures its spirit even in settings far removed from the originals.

The only one of the 10 numbers here I object to is the closer, Chuck Berry's "Roll Over, Beethoven." That's not because I dislike it as a matter of principle. It's hard to dislike any Chuck Berry song short of "My Dingaling"; it's just that "Roll Over" has been beaten to exhaustion and it's no particular revelation that it can be executed credibly on cello. One wishes for something more interesting, such as another traditional piece. (On the other hand, I am partial to Richard Thompson's early "Roll Over, Vaughan Williams," though only its hilarious title links it to the Berry composition.)

That complaint registered, I recommend Walls of Time not only for its outstanding company but for the further evidence it provides of the remarkable durability and malleability of traditional music. Not to mention the truly celestial reading of Bob Dylan's "Lay Down Your Weary Tune."