Metallica and the word “scared” don’t usually go together. But fear was one of the emotions band members felt when they began work on their latest album, “Lulu,” a collaboration with Lou Reed that will be released Tuesday. “That was scary, but it was also so exciting to think, ‘Is he going to tell us what to play? Are we going to know what to play? Is he going to start singing randomly?’” lead singer James Hetfield said in an interview. Reed and Metallica, both members of the Rock and Roll Hall of Fame, first performed together at the hall’s 25th-anniversary concerts in 2009. They found they had amazing chemistry, prompting them to go into the studio together. The concept for the album was the brainchild of Reed, based on the “Lulu” plays (“Earth Spirit” and “Pandora’s Box”) written by Frank Wedekind. … One nation under … Boss? The National Constitution Center in Philadelphia would like to think so. The museum on Independence Mall announced Thursday it will be the only venue outside the Rock and Roll Hall of Fame in Cleveland to host a popular Bruce Springsteen exhibit. “From Asbury Park to the Promised Land: The Life and Music of Bruce Springsteen,” will run at the Center from Feb. 17 to Sept. 3, 2012. Tickets are available on the museum’s website, www.constitutioncenter.org. “It explores one of our most treasured rights, freedom of expression,” Constitution Center President and CEO David Eisner said at a press conference Thursday. Springsteen guitars will be at the exhibit, including the Fender Esquire featured on the cover of “Born to Run,” along with handwritten drafts of lyrics, the outfit he wore on the “Born in the USA” album cover and his 1960 Chevrolet Corvette.