If you do it long enough and well enough, distinctions between tradition and revival begin to blur into nothing that effectively matters. One thinks of Mike Seeger, who has championed old-time mountain music so long that he's now one of its native voices. One thinks, too, of Bob Dylan, as authentic a folk singer as post-folk-culture America will ever produce. And here is the estimable Maria Muldaur, who -- Maria d'Amato when it began -- has been at it ("it" being mostly African-American blues, hokum, jazz and first-generation pop music) since the 1960s. She was good back then (when she was a member of the Even Dozen Jug Band, then the Jim Kweskin Jug Band), and we may safely presume she will just keep getting better and better until the processes of time and biology to which we are all subject silence a wonderful voice at last.

Naughty Bawdy & Blue is the third in a series of Stony Plain recordings on which Muldaur revisits early blues. The first two were focused on country blues, a variety of African-American folk music. The new one explores the so-called classic blues, which amount to the first form of recorded black popular song and also comprise the link between blues and jazz. Classic blues, which dates from Mamie Smith's seminal 1920 recording "Crazy Blues," was an orchestrated horn- and piano-driven, theatrical genre, sung by women (prominently Bessie Smith, Ma Rainey, Alberta Hunter, Sippie Wallace, Muldaur's mentor Victoria Spivey), the songs as often as not composed by African-American professional songwriters and performers who not rarely arranged traditional -- or at least unprotected -- material and claimed credit and royalties for it.

You don't have to know any of this to enjoy Muldaur's hugely good-natured and impressively accomplished performance of songs about bedroom escapades and no-good men. Sometimes the sexual metaphors are so prolific and so outrageous (as in Andy Razaf and Eubie Blake's "Handy Man") that the effect is less erotic than cartoonish, but Muldaur smartly delivers the narrative without resorting to crude parody or condescension. It's not all laughs, either. The infinitely more sober, downright dark "Up the Country Blues" (from Sippie Wallace) chronicles an abused woman's escape to safety from a violent lover. This particular song also demonstrates that even this uptown music did not always eschew rural roots; "Up the Country" borrows lines and structure from Blind Willie McTell's "Statesboro Blues" and Blind Lemon Jefferson's "Matchbox Blues," which themselves may have drawn on earlier models.

Backing Muldaur's throaty contralto on 11 of the album's dozen cuts is James Dapogny's Chicago Jazz Band, one of the finest trad-jazz outfits going. On the remaining cut, Bonnie Raitt shows up to sing with Muldaur on Wallace's "Separation Blues" in front of Dave Mathews's piano and Kevin Porter's trombone. Wherever you drop the (metaphorical) needle, it's good music and great fun -- and vice versa.