“Blue might very well be the best album ever made,” Brandi Carlile said of Joni Mitchell’s 1971 masterwork, which Carlile is performing at the Walt Disney Concert Hall. The idea for this unusual tribute concert came to the Grammy Award-winning Carlile after she took part in Mitchell’s 75th birthday celebration. “Hearts on sleeves and voices raised,” Carlile told JamBase. “Let’s do this one for Joni.” —E.C.