Zeppelin as a Seventies kid – and bold enough to seize "Smells Like Teen Spirit" as her own (on 1992's Crucify EP) – she recognized that grunge's uneasy blend of emotional distress and sonic kicks represented a state of mind as well as a guitar sound.

On From the Choirgirl Hotel, Amos comes clean with the rock & roll that's always driven her, from as far back as when she stormed out of her rehearsal room at the Peabody Conservatory. Whereas 1994's Under the Pink and 1996's Boys for Pele strove to extend Amos' voice-and-piano foundation into different areas – R&B and dance – From the Choirgirl Hotel closes up shop and starts over with a live-band recording. A woolly jam dynamic pervades Hotel, from the paisley metallicism that kicks off "Spark" (the current single) to the grooving dream world of "Liquid Diamonds." Throughout the album, Amos throws herself and her various keyboards into bass-drum-guitar ensembles augmented by percussion loops and string sections. In the past, all elements of her arrangements answered to Amos and her keyboards; now, she replaces that hierarchy with rock interaction. On From the Choirgirl Hotel, she's just one of several tenders of her own sound garden.

But for all of her new material's bracing accessibility, very little is very straight-up. Amos remains the girl whose background in European piano literature encouraged her to hear the unforgiving structures of the Baroque era, the vast spiritual and melodic vistas of the Romantic period, and the knotty imperatives of twentieth-century experimentalism as one ongoing compositional story – not a bad basis, thank you, for art rock with guts. And although these mixes don't hesitate to occasionally bury her voice, Amos often still sings like the coloratura president of Robert Plant's fan club. On songs like the technoish "Hotel" and the beat-happy "Raspberry Swirl," moreover, she screws with timbre, lyrics and meter in the proud pop-collage tradition of Nineties artists like My Bloody Valentine, the Smashing Pumpkins, Björk, U2 and Garbage. Other times, Amos is more nostalgic, as on "She's Your Cocaine," which feels like the music of the hardest-working bar band – on Saturn.

Amos hasn't completely abandoned ballads, not with showpieces like "Northern Lad," as well as "Jackie's Strength," the center of this consistently aliv