Although Nashville's economic and artistic doldrums add luster to the Judds' overnight stardom, this mother-daughter harmony group would shine in any era. The Judds' third album, "Rockin' With the Rhythm" (RCA-AHL1-7042), may only refine their earlier successes, but it is nevertheless a satisfying record. After all, it would be foolish for an act only two years old to tamper with the creative ensemble of producer, arranger and musicians that has helped the Judds fashion the most seductive sound in country music.

The Judds' velvet harmonies and Wynonna Judd's sultry lead vocals are still the heart of that sound. As usual, Brent Maher's crystalline production draws the listener straight to their voices, creating a sense of shared emotional intimacy. When Wynonna sings "Grandpa, Tell Me About the Good Old Days," the conversational nuance of her delivery and Maher's warm production make it seem as if she really is on the back porch talking with the old man.

That song also reflects the Judds' ability to pick material that is both melodically strong and resonant with their own lives. When Wynonna tenderly asks grandpa for details of a simpler past, her plea underscores the distance between the Judds' traditional mountain upbringing and the modern stardom they've achieved and pressures they face. In fact, the Judds' vocals seem so uncalculated and sincere that even the conventionally romantic ballads they favor sound strikingly personal, even autobiographical.

When the Judds' close mountain harmonies give way to Wynonna's lead singing, she offers a more modern and assertive vocal presence indebted to blues, pop and rock. That seamless flow from the traditional to the contemporary is also evident in band leader Don Potter's superb arrangements. It's not surprising that the Judds call Potter "the third Judd," because his innovative and mostly acoustic arrangements have been essential to their success. Potter's arrangements frame the Judds' vocals with old-timey simplicity and then add a sparkling instrumental verve that is pure pop.

Potter uses his own rhythm guitar and bass and drums to create rhythmic support, decorating the sound with sparse and elegant touches of steel guitar, dobro, piano and dulcimer. In Paul Kennerly's soulful "Have Mercy" and "Cry Myself to Sleep," Potter and the band sustain a taut and funky rhythmic snap that emphasizes the songs' underlying sexual tension. On these numbers, Wynonna sings from deeper in her throat, succumbing to bluesy growls when words fail her.

Although most of their material comes from Nashville writers like Kennerly, the Judds stray into rock 'n' roll for a lighthearted frolic on the old Lee Dorsey novelty hit, "Working in the Coal Mine." Better is their version of British rocker Mickey Jupp's lovely "Tears for You." On this swaying ballad, the Judds' harmonies dramatically stretch like the softest butter-coated taffy.

Not surprisingly, other labels have been on the lookout for family harmony groups that might duplicate the success of acts like the Judds, the Whites and the Kendalls. From Lookout Mountain, Ga., come four sisters whose self-titled debut album, "The Forester Sisters" (Warner Bros. 25314-1), has already yielded two big country hits. Both their first hit, "When You're in Love," and "Mama's Never Seen Those Eyes" capture the ingredients of the Foresters' commercial appeal: cheerful church-bred harmonies, bouncy country-rock rhythms and irresistible choruses. Kathy Forester sings most of the group's leads, and though her husky delivery is pleasing enough, it is not sufficiently distinctive to breathe any extra life into these songs. When Kim Forester takes the lead on a swinging blues called "Dixie Man," her singing is just too lightweight and girlish to project the earthy passions of the lyric.

It's the Foresters' upbeat harmonies, forming a kind of collective women's voice, that turn most of their material into engaging country-pop. J.L. Wallace and Terry Skinner's production is just fine when it sticks to acoustic guitars, a sawing fiddle and those four voices. At times, however, their production is just too forceful and dense and they pile on the keyboards and guitars, revealing an unfortunate insecurity about the appeal of a good song delivered with tight harmonies.