Hilary Hahn’s career is the stuff of classical-music legend: By age 12, she’d played violin with the Baltimore Symphony; by 19, she’d graduated from the ultra-elite Curtis Institute of Music and made her Carnegie Hall debut; and though she’s now just 34, she has played with pretty much all of the world’s major orchestras (945 concerts, to be exact). But Hahn isn’t solely a marquee name. She’s also a contemporary music advocate, having most recently commissioned 27 short-form works from living composers and recorded them for her new album, In 27 Pieces. After performing in South America and Europe last fall, Hahn begins a U.S. tour in February premièring the final 14 pieces. hilaryhahn.com.