There is a curious reverse-symmetry to the careers of Fiona Apple and Liz Phair, both of whom release new albums today. Both are products of the mid-1990s, a post-grunge boom era for female talent. Early on, however, they represented opposite ends of it. Apple was the made-for-MTV star with the bluesy voice, underwear-clad videos, and adorable teen angst. Phair was beloved by the indie rock crowd for her lo-fi sensibility, deadpan sexuality, and revolt against the privileged suburbs of her youth.

Starting, as they did, from such different places, the two were rarely talked about in the same breath. In the intervening years, however, they’ve virtually switched places – or attempted to, anyway. Apple has repeatedly rebelled against her early success and the forces that gave it to her. Most (in)famous was her tantrum at the 1997 MTV Video Music Awards – at which she won the Best New Artist award – where she declared, “this world is bull-,”and, quoting Maya Angelou, instructed young women to “go with yourself.”

Go with herself she did. Her 1999 album “When the Pawn …” had a 90-word poem for a title and complicated arrangements – alternately jazzy and carnival-esque, compliments of producer Jon Brion – that ensured she would be a tough sell to the teen audience that had embraced her debut. “When the Pawn …” sold only a million-plus copies domestically, as compared to 3 million for “Tidal,” her debut.

Phair’s career, meanwhile, has been marked by repeated – and ever more desperate – efforts to court the mainstream. Her most recent (and egregious) effort was her eponymous 2003 album, which included work by Avril Lavigne songsmiths the Matrix. The 30-something Phair was trying to remake herself in the image of a teen pop sensation, or so it seemed to the galled indie press that had once championed her.

New albums find both Apple and Phair arriving, for better or worse, at the destinations they set out for. Apple’s “Extraordinary Machine,” begun six years ago, was adventurous enough to land it in major-label limbo. And it might well have remained there had not an early copy mysteriously leaked this spring, prompting a fan-driven “Free Fiona” campaign and an avalanche of admiring press.

Whether or not Sony withheld it (the company now claims it would have released any album Apple deemed finished), the delay isn’t all that surprising. The album – both the leaked copy produced and arranged by Brion, and the final one, produced mostly by Mike Elizondo (best known for his work with Dr. Dre and Eminem) – is by turns moody and whimsical, and challenging enough to extinguish all hopes of commercial success. It’s also the best thing Apple has done – by a wide margin. Her lyrics to a new song serve as an apt description: “My method is uncertain, it’s a mess but it’s working.”

Wisely Apple has stuck with the Brion-session version of the title track, which opens the album. With its mannered strings, slinking bass, and WB cartoon woodwinds, the song will send you scouring the P2P networks for the other leaked Brion-produced tracks. Apple’s lyrics are equally charming: “Be kind to me, or treat me mean / I’ll make the most of it, I’m an extraordinary machine,” she sings playfully.

Despite her professed emotional adaptability, Apple can’t disguise her broken heart after splitting with longtime beau (and “Magnolia” director) Paul Thomas Anderson; the shards are littered all through the album. On “Tymps (The Sick in the Head Song),” over tinkling marimba and clavinet, she ponders: “I’m either so sick in the head I need to be bled dry to quit / or I just really used to love him. I sure hope that’s it.” Her former feelings, both bitter and fond, are confirmed on “Parting Gift”: “The sign said stop, but we went on wholehearted / it ended bad, but I love what we started.”

Phair’s new album, “Somebody’s Miracle,” succeeds much less. It’s harder to make a bid for new fans than to shed old ones. Phair’s strategy is not to disown her indie past, but to try to bring it into line with her pop present. In a six-minute DVD, titled “Liz Phair: A Retrospective,” included in the press kit, she explains that she’ll “always be a boundary pusher, it’s just what I do.”

We’re supposed to understand her mainstreaming as just another form of rebellion. But it sounds anything but rebellious. The songs are relentlessly poppy and superficial, full of bright, country-tinged guitars and brighter sentiments, closer to Shania Twain than the Liz Phair of old. She’s not pushing boundaries so much as reinstating them.

The lyrics to “Count On My Love” are representative: “Blue eyes, bluer than the blue sky / shining down like sunshine, everywhere you are / for you I only want the best / you only have to ask and I’ll be there for you,” she beams. This from the woman who once courted men by singing, “I want to f-you like a dog / I’ll take you home and make you like it.”

There is one relapse, and it makes for a fascinating glimpse of what might have been. “Table for One” is the tale of an alcoholic mom making only a minimal effort to keep up appearances. “I hide all the bottles in places / they find them, confront me with pain in / their eyes, and I promise that I’ll make some changes,” she sings. It’s confessional, honest, self-disgusted, confused – a mature version of the Phair fans fell for in the first place.

The retrospective DVD ends with a line eerily reminiscent of Apple’s “go with yourself” credo. “The best advice I can give to anyone getting into this profession is be yourself,” Phair says, “and that’s all I’m trying to live up to.” She sounds earnest, which is just as well, considering her current sound will please few besides herself. Just as she has the right to change, longtime listeners have the right to feel deserted and disappointed. But former Phair fans needn’t lose heart entirely. They may find just what they’re looking for in an artist named Fiona Apple. Liz Phair plays

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