The chances are slim that Julian Casablancas will croon his comedic Saturday Night Live tune “Boombox” at the Beaumont this weekend. But who knows? At this point, Casablancas seems confused about what he’s doing with a solo career anyway. After leading the Strokes into the spotlight 10 years ago as one of the formative bands of the millennium, Casablancas embarked on a natural process: He hit 30, freaked and bolted. Phrazes for the Young, his 2009 solo album, is full of the unleashed energy that the Strokes’ last albums meticulously repressed. So expect ’80s synths, the familiar monotone warble, a Lower East Side punk drone and maybe some songs you know — Casablancas whipped out some Strokes numbers at a recent performance in New York. Of course, as “Boombox” promises, 10 bucks says he’ll be wearing fingerless gloves.