After four solo albums, actor-turned-singer Billy Bob Thornton has proven that his devotion to making music equals his devotion to making movies. Now he branches out a bit as frontman for The Boxmasters, a trio that aims to combine Bakersfield twang with the spirit of rock’s 1960s British Invasion. The results are mildly intriguing, although 76 minutes of music spread over two CDs (one originals, one covers) is a bit much. The band’s own songs aren’t nearly as clever as the nifty reinterpretations of chestnuts like The Beatles’ “I Wanna Hold Your Hand” and The Who’s “The Kids Are Alright.”