Alanis Morissette/Avril Lavigne

So-Called Chaos (Maverick)/Under My Skin (Arista)

The homogenization of female voices in the Top 40 -- thanks to ProTools, risk-averse record labels, and malleable starlets eager to conform for fame -- is one of the most disturbing recent trends in music. In fact, perhaps the only thing more disheartening in mainstream radio is the almost complete absence of women on rock stations.

This male-dominated, uniform music culture minimizes the feminine perspective on relationships, ideas, and emotions -- which is why the new albums from Alanis Morissette and Avril Lavigne are so welcome. Although the Canadian angst twins are sometimes derided for lyrics that are weak (Lavigne) or ostentatious (Morissette), the two aren't shy about copping vindictive 'tudes toward those who wrong them -- making for welcome displays of assertiveness amid all the lightweight diva fluff.

Lavigne's second disc, Under My Skin, certainly sounds more confident than the dramatic high school emo atmospheres of her debut, Let Go. Its lead track, the Evanescence-like "Take Me Away," features Lavigne wildly screaming atop jagged chords, and "He Wasn't" is a bratty metal workout sweating to the Donnas. But levity abounds amid this crunch: "Together" and "My Happy Ending" feature docile piano swells before ripping into feisty choruses. Lavigne's boy-crazy lyrics have improved mightily as well, highlighted by the so-long-asshole! ditty "Don't Tell Me" ("Don't think that your charm and the fact that your arm is now around my neck/Will get you in my pants/I'll have to kick your ass and make you never forget").

Morissette also managed a successful transition from mall-haired bubble-gum pop star to credible singer-songwriter, with a few occasional detours down Pretentious Street ("Thank U") and Overindulgence Avenue ("Uninvited"). Chaos, however, is a gimmick-free set of tunes that are her strongest compositions in years. "Eight Easy Steps" and "Excuses" are rousing rockers built on blazing chords and loopy keyboard flourishes, while the gently syncopated beat of the midtempo "Not All Me" and minimalist, Tori Amos-style "This Grudge" illustrate her softer side well. There are a few blunders -- "Knees of My Bees," especially, is a bit too overbearingly hippie, with its sitar and awkward phrasing ("You make the knees of my bees weak/Tremble and buckle"). But the best parts about Chaos and Skin are their flaws -- a clunky line here, a bizarre pronunciation there -- because their blemishes remind listeners of just how perfect imperfection can be.