Metallica and Lang Lang rehearse for THE 56TH ANNUAL GRAMMY AWARDS music industry's premier event takes place Sunday, Jan. 26 (8:00-11:30 PM, live ET/delayed PT) at STAPLES Center in Los Angeles on the CBS Television Network. Photo: Heather Wines/CBS ©2014 CBS Broadcasting, Inc. All Rights Reserved

Musician Kirk Hammett of Metallica performs onstage during The Big 4 held at the Empire Polo Club on April 23, 2011 in Indio, California.