LINDA RONSTADT'S new album, "Dedicated to the One I Love," is a collection of bedtime songs for children, and yet it's the boldest, most innovative recording of her career. The knock against her has never been her voice -- which is a big, sumptuous soprano -- but rather the play-it-safe approach of her interpretations. Whether redoingthe songs of Chuck Berry or Elvis Costello, George Gershwin or Arthur Sullivan, the California singer always conformed as much as possible to audience expectations. On her new album, though, she has taken the songs of the Shirelles, the Ronettes, Queen and the Beatles and rearranged them so radically that they've been transformed from anthems of adolescent hormones into infant lullabies.

The impetus for this project began three years ago, when Ronstadt was recording the old Beach Boys song, "Don't Talk (Put Your Head on My Shoulder)," for her "Winter Light" album. "I was singing that song," she remembers, "and I had the same feeling you have with a newborn -- you're struck dumb and still. When you're holding a baby, you want to pat them on the back and say, Don't talk; just put your head on my shoulder.' I then realized that a lot of old rock songs could also work as lullabies. I wanted to do a whole record with that approach.

"When you think about it, there are a lot of similarities between teenage love and the love for a newborn baby -- that is, if you're doing it right. There's that total, unquestioning love and all that anticipation about what will happen next. We think of sex as the end point, but it's really just the beginning. Motherhood is really the fulfillment of romantic love."

Ronstadt, who appears with Marvin Hamlisch and the Pittsburgh Pops Orchestra Tuesday at Merriweather Post Pavilion and Aug. 3 at Nissan Pavilion, chose songs that would work as lullabies without changing the lyrics. She even preserved the original tempos and arrangements. "You have to respect the riffs and phrasing of those songs, because that's what they're built around; if you take that away, you don't have anything left. The exception is the Beach Boys stuff, where the melodies and chord changes are as sophisticated as anything by Gershwin and Rodgers."

What she did change was the vocal attitude and instrumental timbres. Rather than singing with the agitation of youthful lust, she delivered the songs in the soothing tones of maternal devotion. To supplement this whispery crooning, the album contains no electric bass, no drums and no guitars at all. Instead, the arrangements feature strings, piano, harp, flute and the glass armonica -- a Benjamin Franklin invention in which different size glass bowls are mounted sideways on a hand crank and played with wet fingers. The result is a lulling, nap-time ambience unlike anything else in the singer's catalogue -- or in the rest of pop music, for that matter.

Ronstadt is the single mother of two adopted children -- a 5-year-old daughter and a 2-year-old son (she refuses to give their names) -- and she tested out these redefined lullabies at home. "When my son was born, and I started singing to him," she recalls, "all these songs came out. I'd sing him Dedicated to the One I Love,' because that helped him go to sleep, but during the day, we'd sit in a rocking chair, and I'd sing We Will Rock You' very quietly to the rhythm of the chair. So when we recorded the song, I thought, what percussion can we use to be true to the beat of the song and also true to the quiet intimacy of a lullaby. So we sampled a heartbeat and my daughter sucking on a pacifier."

Helping Ronstadt re-create the "girl-group" harmonies of the Shirelles' "Dedicated to the One I Love" and the Ronettes' "Be My Baby" and "Baby, I Love You," was Valerie Carter, a legendary L.A. singer of the '70s who has recently bounced back from personal problems to release her first album in 18 years. Ronstadt returned the favor by singing on that album, "The Way It Is." "I sing with Valerie whenever I can," she says, "because there's something about the quality of her voice that blends very well with mine. It brings things out of my voice that I wouldn't do if I weren't singing with her."

The biggest influence on Ronstadt's current music, though, is the Beach Boys' Brian Wilson. "When I was recording Cry Like a Rainstorm,' " she recalls, "we were working on Adios,' a Jimmy Webb song, and we decided we wanted this Beach Boys sound on it. So I said, I know Brian; I'll just call him up.' Back in the '70s, he wasn't living at home, and he used to come to the back of my house and say I need 27 cents to buy grape juice.' So we'd go to the health food store and get some grape juice, or we'd go to the laundromat together.

"I've always said that the guys I love are the three Bs -- Bach, Beethoven and the Beach Boys. And after working with Brian on Adios' and seeing how he layers voices and instruments, I wanted to use that approach on more of my stuff. So I recorded his Don't Talk (Put Your Head on My Shoulder)' on Winter Light' and his In My Room' on the lullabies album. It's no secret that Brian had a troubled childhood, and when he sings about feeling safe in his own bedroom, it's tremendously moving."

The singer recently collaborated with another of America's best songwriters, Randy Newman. When Newman recorded his satiric version of Goethe's "Faust" in 1995, he gave his old friend the character of Margaret, "the poorest, nicest and most beautiful girl in South Bend." She was so taken with the songs that she redid one of Bonnie Raitt's numbers in "Faust" and made it the title of the 1995 Ronstadt album, "Feels Like Home."

"Randy's stuff is very difficult to sing," she admits. "I'm a drooling fan of his, because there's always so much profound emotion going on in his songs that I take them as a challenge, and I wrestle with them. But whereas Brian's stuff sings as fluidly as the Gershwin stuff, Randy likes to kill singers."

This year Ronstadt reunited with Aaron Neville, her duet partner from the "Cry Like a Rainstorm" album, for a PBS-TV special from the White House. "I usually don't like to sing in such an exclusive setting where my fans can't buy a ticket," she says, "but the election's coming up and I don't want any more Republicans getting in." LINDA RONSTADT -- Appearing Tuesday at Merriweather Post Pavilion and Aug. 3 at Nissan Pavilion. To hear a free Sound Bite from "Dedicated to the One I Love," call Post-Haste at 202/334-9000 and press 8121. Prince William residents, call 690-4110.) CAPTION: Linda Ronstadt sings for children on her new album.