Superstar can't shake 'Loose Cannon' label (Updated January 30, 2013)

Before Tori Amos, Sara Bareilles, Lady Gaga and Alicia Keys, there was Fiona Apple. For decades she has resisted auto-tuned vocals, synthesizers and digitally altered tunes in favor of showing herself as an accomplished pianist and vocalist. With rich arrangements and melodies, not to mention a wider audience thanks to some jazz-tinged material, she was practically the overnight sensation of the late 1990s.

If there's one thing that can be easily explained about Fiona Apple, it's her angst-ridden lyrics. Her parents separated when she was just four years old. She taught herself piano by eight, and was playing and writing songs at the age of 12, all while trying to work through a traumatic childhood that included a rape at the age of 11. She dropped out of school and moved to Los Angeles at the age of 16, and earned a contract with Sony Music just two years later.

A debut album, "Tidal," bowed to critical acclaim in 1996 behind hits like "Criminal," "Shadowboxer," "Sleep to Dream" and "Never is a Promise." But while accepting the MTV Video Music Award for "Best New Artist" in 1997, she gave an acceptance speech later deemed ungrateful and "ridiculous" by various media publications. Simply put, Fiona Apple was barely brand new to the music industry and had already been labeled a "loose cannon."

Continuing to define categorization, Apple chose a 90-word "poem" as a title to her sophomore album "When the Pawn…" in 1999. It was the beginning of more upheaval in her career, as the project didn't fare well commercially, and she later had a meltdown in the middle of a performance at the New York City Roseland Ballroom that led her to contemplate retirement. An extended hiatus and a series of delays on her next album led to "Extraordinary Machine" not being completed until the fall of 2005, though it did garner a Grammy nomination for Best Pop Vocal Album.

Apple's latest album, 2012's "The Idler Wheel…," was shrouded in secrecy until its completion – even from her label. That fall she famously postponed her South American tour to care for her dying dog.