Fiona Apple was only 18 when her first album, "Tidal, " was released.

NPR: Fiona Apple: 'Extraordinary Machine'

Ms. FIONA APPLE: (Singing) O'Sailor, why'd you do it?

NPR: Fiona Apple: 'Extraordinary Machine'

Fiona Apple and Norah Jones, each a decade or more into their careers, know this problem and the question it implies: How, without calcifying, do you remain the performer who initially enticed your audience?

NEWYORKER: Revelation Road