Record buyers have become understandably skeptical of new releases accompanied by an inordinate amount of hype: Too often, all that smoke covers an absence of fire.

Not so with Carlene Carter, who last year produced a truly stunning debut album that required no publicity-department smokescreen, and deserved all the media coverage it earned. When she made her performing debut at the Bottom Line in New York, with an approving audience of industry types in front of her and Graham Parker's Rumour behind her, it became clear that Johnny Cash's stepdaughter had left Nashville behind.

There is very little country in her performing, which is a curious blend of New Wave and Las Vegas. She is capable of a sneering delivery, perfect for the Nick Lowe and Elvis Costello sons she sings; but she also has the movie-star looks and the low, sensuous voice of a lounge singer. Only a trace of her heritage emerges, for example, when her voice quivers with emotion as she sings the word "love" with two syllables, just like her musical forebears, the legendary Carter Family.

"Two Sides to Every Woman" (Warner Bros. BSK 3375), Carlene Carter's second album in less than two years, reveals yet another talent that is unusual in a singer of her tender age: She can write. Seven of the nine cuts on the album belong, at least in part, to Carter, including the opening number, "Do It in a Heartbeat," which her husband, Nick Lowe, and guitarist John McFee helped to write. Her lyrical range extends beyond the narrow country parameters of heartsick women and a faithless lovers and into ambitious areas such as intentional irony, feminism and even lust. Tammy Wynette she is not.

Musically, "Two Sides" is slicker than the first album. In the hands of New York producers and session men, without Rumour to set her straight, Carter occasionally succumbs to the charms of studio hooks and flourishes. Not disco, thank God, but definitely not as raw and torchy as the first album led us to believe she would be.

Crystal Gayle is a product of Nashville, and a product she is. As Loretta Lynn's sister, she too was born into the country tradition, but instead of striking out on her own, she lapsed into a vapid mainstream country formula and has shown neither the ability nor the inclination to try anything else. She's been quite successful commercially, with both albums and singles, but she allows herself to be disgracefully packaged by her iron-handed producer, Allen Reynolds. She has, to her record company's delight, become a one-woman hit factory.

Unlike Carlene Carter, Crystal Gayle has become a creature of the studio. She relies on banks of strings and horns for her sound, and other people's writing for her lyrics. "Miss the Mississippi" (Columbia JC 36203), her latest release, proceeds according to the formula, from the Francesco Scavullo photo on the cover to the Sheldon Kurland Strings on the inside. It is, frankly, the worst thing to happen to country music since Dolly Parton went disco.

Gayle is capable of good music -- even great music -- as she demonstrated so elegantly with "Don't It Make Your Brown Eyes Blue." Her voice is her instrument, and she can use it, when she's given permission. On "Miss the Mississippi," Gayle's voice must compete with a robust accompaniment of horns, strings, drums, guitars and harmony vocals. Unfortunately, for the most part, her thin, lilting voice is not up to the challenge, and she ends up sounding like a soloist battling the Mormon Tabernacle Choir.

But Gayle seems more concerned with fame than with critical acclaim, and fame she undeniably has. She has two albums and two singles on the Billboard country chart now, and she just appeared on the Bob Hope special filmed in the People's Republic of China. That's a long way from her birthplace in Butcher Hollow, Ky., and a ways away from the Mississippi she claims to miss.

But then Crystal Gayle has sounded less and less like a country girl and more and more like a wind-up doll with each passing release. It's enough to make your brown eyes blue.