THE NEW ROSANNE Cash album, "Interiors," doesn't sound quite like a country album. In her debut as a producer, Cash has stripped her songs down to a quiet, intimate sound built around guitar, bass and her voice.

"It sounds folkish to me," she admits. "The songs were stark and intimate in themselves, and I insisted that the arrangements should follow that. I was adamant that I didn't want a full drum kit on more than one or two songs."

In keeping with the pared-down sound of the album, Cash has embarked on her first-ever all-acoustic tour. When she comes to the Birchmere Saturday, she will be joined only by guitarist Steuart Smith and bassist Jim Hanson, who both play on "Interiors."

"The songs are real personal," Cash says, "and they lend themselves to this kind of performance. I'm excited, but I'm also real scared, because I'll be up there without much protection."

As Cash once said, rock 'n' roll is about the excitement of your first or second love, but country music is about the struggle of your fifth, sixth or 10th relationship. The daughter of Johnny Cash and granddaughter of Mother Maybelle Carter, Cash has country music in her blood and her "Interiors" tackles the genre's classic themes, even though it does so in unorthodox, innovative ways.

It's the first album where Cash wrote or co-wrote all the songs herself, and she sees the 10 tunes forming a unified song suite. "A continuous concept runs through the album," she says seriously, then laughingly adds, "or maybe, I should say, 'a relentless concept.' "

Most of the songs use the internal/external metaphor suggested by the title to describe a relationship -- or an individual life -- that seems happy and successful on the outside even as it's crumbling apart on the inside.

"On the Inside" describes "the tears and debris" of a couple's private life, while "On the Surface" depicts how they create a facade like "actors on the stage." Another song expresses the wish to be a "Real Woman" instead of a princess who fakes her smile. "I smile but I'm not even there," she sings in "Land of Nightmares"; "Paralyzed" describes that moment when "the pretenses between us" are dropped.

"That metaphor about the split between image and reality appealed to me," she says, "because it's so all-encompassing; it covers so many situations. That theme has always been in my writing, but it's more obvious now, because I've worked hard to peel away all the distractions and write more from my own interior. I think that split can be healed, although I'm not sure how. All I know is that fear causes the split, and just being brave enough to explore it can help.

"For example, the song on the album, 'This World,' was a verbatim account from my life. I really couldn't sleep at night after reading about a child abuse case. I said, 'What am I supposed to do about this?' and Rodney said, 'You're a writer; write about it.' So that's what I did."

Rodney is Cash's husband, Rodney Crowell, a country star in his own right. Some listeners inevitably assume that every relationship song Cash or Crowell write is about their relationship.

"If I sat down and worried that people were going to assume these songs were strictly autobiographical," Cash says, "I would get scared and never write anything . . . so I just go ahead and let the chips fall where they may."

Some of the songs are autobiographical, of course, but many more are possible autobiographies. "Sometimes I write about something I haven't actually experienced yet," Cash explains. "If I'm in a crisis and I see several possible outcomes, I might write a song about one of the options, even if it hasn't really happened. Or sometimes I'll write a song and it's not until six months later that I'll listen to it and realize the full extent of what I had said to myself.

"A friend of mine once told me that she came home from work one day and just fainted without warning or explanation. A little later her husband confessed that he was having an affair. It was like her body had received the information before her mind did. I think that happens all the time. It's almost as if your intuitive side is a more fully developed being who's leaving notes in hopes your denser self will eventually pick them up. The intuitive side writes the songs."

With a laugh, she adds, "At least it writes the good ones; the cognitive side writes the dogs."

As Cash wrote these new songs, she had a strong sense of what they sounded like in her head. "I didn't feel like I had a choice about producing," she says. "I had this group of very personal songs, and I wanted the arrangements to reflect the songs exactly. I couldn't see turning it over to a producer who would come up with pop, perky versions. If that had happened, we would have lost the songs; their vulnerability would have been completely obscured. I don't think any other producer would have made a record that was this stark and unbalanced."

Cash is quick, however, to credit Steuart Smith for helping her with the arrangements. Smith is a Northern Virginian who played in many D.C. bands before moving to Nashville.

"Rodney was doing a New York recording session that Steuart played on," Cash recalls, "and when Rodney came home, he said, 'I've found the perfect guitarist for our music.' And he was right. Steuart plays everything as if it were an intrinsic part of his nature; nothing is contrived. He worked so hard on this record. Whenever I needed support or someone to bounce ideas off of, Steuart was always there."

ROSANNE CASH -- Appearing Saturday at the Birchmere. Call 202/432-0200.