In the last four years, Liz Phair got married andhad a baby. The Chicago alterna-pop fave also made a terrific record that is arguably more mature than her last two. But the first point isn't inextricably linked with the second.

Phair figures the press is falling over itself with birth and baby metaphors in describing her superb, wildly diverse new album whitechocolatespaceegg, because it's in conflict with the whole "shallow image" of her as a sexual adventuress -- "That's not the person you picture having a kid and being a responsible mother."

But Phair, who comes to Avalon tomorrow, wants people to wade into the deep end of her music.

You can be a full woman and have many different aspects all under one roof and grow and change and keep them all together," she said in a recent interview from her home in Chicago.

"But I think it's just a press thing, a male press thing that, 'Oh, you're a mommy now.' They just picture soggy breast pads and it's the antithesis of what they like, which is the cute come-on."

Anyone who listened closely to Phair's critically acclaimed indie debut, 1993's Exile in Guyville, or its glossier, more underrated 1994 follow-up Whipsmart, knows that Phair was never just about the cute come-on. She may have been sexually explicit, but never shallow.

The same can be said of whitechocolate whose stylistic range includes a cynical sing-along drinking song, '80s-style keyboard-heavy new wave and super catchy pop. Whether she's singing in the guise of a "Big Tall Man" or nakedly exposing her post-partum marital woes in the heart-rending "Go On Ahead", Phair employs a directness, a humor and an ardor for considered lyrical construction that is uniquely her own.

Although the diverse musical nature of the album wasn't specifically planned, Phair said, "What was intentional is that I was totally willing to let anything happen in the studio that felt spontaneous."

The lyrics include the passage, "I never realized I was so dirty and dry / 'til he knocked me down, started dragging me around in the back of his convertible car / And I liked it."

"That seems to be the lightning rod for this album," she said, "and no, I don't care. I really don't. Because if the context were really understood, if it upset someone, that would be the kind of person that I wouldn't care about anyway. I think it's just a general, quick read that leads people to believe I'm saying 'Ooh, hit me, hurt me.' It's really obviously more than that, it's an empowering song in my mind."

"It's more about stepping out of the need for men to be so sensitive that you have to have this safe, safe ground to reveal your feelings and it's about me feeling strong enough to take someone on. People that read into stuff with absolute literal eyes, I can't help them."

Oddly enough, it again didn't occur to Phair that songs like "Johnny Feelgood" and others with unprintable titles from Exile, might not go over well at the more PC-perceived Lilith Fair, at which she performed this summer.

"Again, this is how stupid I am," Phair said, laughing. "It was the first time I ever understood why my songs had the impact that they had."

She said she used to wonder what the big deal was until she heard herself singing songs like "6'1"" from Exile with confrontational lyrics like "and I hated you".

She did manage to find friendly faces among those in the crowd awaiting the more sedate lkes of Natalie Merchant: "I'd just sort of shift my gaze around until I found my little pockets of fans and sing to them."

Playing Lilith helped Phair tremendously in overcoming a debilitating stage fright.

"I've always buckled under the idea that there are these huge expectations for me and, will I live up to them?" said Phair. "And this (Lilith) was so neutral. They didn't expect anything, you just gave them whatever you chose to give them and that just gave me this sense of control and power and I got excited, and after the first week I learned how to be tough and exciting without feeling, like, I was, like, you know, upsetting them."

Phair is aware that part of her popularity is attributed to her ability to tap into emotions that a lot of women her age feel.

"When I write, it's really to represent a lot of us, in a way, and I'm pulling at emotions that I feel are things that I run into again and again in my life and everybody else does, too."

Liz Phair performs at Avalon, Boston, tomorrow night at 9. The show is sold out. WBCN-FM (104.1) will broadcast the performance live.