She told us from the start - when she was lead singer of the Stone Poneys back in 1967 - that she traveled to the beat of a different drum. For Linda Ronstadt, some 27 years later, clearly the beat goes on. After singing folk rock in the 1970s and light opera, jazz, and pop standards in the 1980s, Ronstadt mined her Mexican roots to create three Spanish-language albums. Her latest musical missive is Winter Light, which includes several classics from the 1960s. When asked to comment on a theory, included in a glowing New York Times review, behind her choice of 1960s songs, this maverick says she generally doesn't read reviews or anything else written about her. "[Critics] think they know where I'm coming from, and they're always wrong!" she declares.

She then good-naturedly attempts to articulate the process she does go through when choosing a song to record. "I kind of get a general feeling from a song," she offers. "I'm not quite sure what - sometimes, it's just a succession of mixed emotions, and if I like it well enough and it pushes enough little emotional buttons, I'll put down a track and then it begins to instruct me.... There might be a chord that reminds me of something my sister's going through or some chord that reminds me of something I did yesterday or a chord that reminds me of a girl-friend's marriage failing apart. And there might even be a line that I deliver specifically to that person."

Ronstadt says it's her longtime friend Emmytou Harris who "can find songs better than any human being on the planet." Together with Dolly Parton, the threesome sat on the living room floor of Ronstadt's San Francisco home last November and selected songs for the follow-up to their 1987 multiplatinum, Grammy Award-winning album Trio. "All of us are happy to base our decisions on what the music demands, what suits the trio best," Ronstadt reports. And the result is something she can "actually listen to with a certain kind of admiration that I would [never have when] listen[ing] to my own stuff."

In fact, she says, she never listens to her own music once she has left the studio. ("My car trunk is loaded up with opera C.D.s. And, as a matter of fact - this is how narrow I am ­ they're only Maria Callas.") When not listening to Callas, Ronstadt sings: "I sing walking down the street. I sing unconsciously. I used to have a boyfriend who was kind of embarrassed, and he'd say, 'You're always singing.' I'd go, 'I'm sorry, I don't realize it.' I just do it. It's a biological necessity. There isn't an OFF button."

Surprisingly, the veteran performer says she's not so sure how she would fare if she were starting her career today. "It's so fast and unforgiving, and there aren't any places to learn," she complains. "Sometimes you need to make three records in a row where you're just kind of learning." Indeed, the 47-year­old Tucson, Arizona, native says the opportunity she had to explore her past, with her Mexican records "made me able to go into that place where I am most authentically myself and tune myself up a bit, make myself stronger. So pop music - when I returned to it - was relatively easy. It was still interesting, and it was still thrilling to do; it was just a bit more achievable than it was before."

She says she hasn't heard Frank Sinatra's popular Duets album but confides that she was asked to sing with Old Blue Eyes. Producing friend Jimmy Webb's new record took precedence, she explains, saying she would love to do a duet with Sinatra - if she could produce it. Then she adds, "It just hasn't commanded my attention the way that it would if Aaron Neville called me up and said, 'Hey do you want to sing, you know, the phone book?' Fine, let's get together and sing the phone book. No problem. Aaron's my guy."

While she freely admits she loves to gossip, getting her to say much about her private life is impossible. When you ask her about becoming a single mom - she reportedly adopted a baby girl named Mary Clementine about two and a half years ago - she says, "I've never told anyone that. You only know about it from hearsay. It may or may not be true, but you won't hear it from me. I never talk about my personal life." Which means you can forget getting any informa­ion about her love life. (Her last reported relationship was with director George Lucas.) What she will say is that for her next album she plans to sing accompanied by glass instruments from the eighteenth century and that she's actively attempting to go live "where there's no electricity or cars." So she'll be walking, rather than driving, down that road less traveled.