When Matt Valentine (vocals, guitar, harmonica) and Erika Elder (vocals, mandolin, lap steel), aka MV + EE, tour with a band, they call it the Golden Road. But if you drove a car the way their recent releases veer between styles and sounds, you’d get pulled over. There are no songs on last year’s LP Ragas of the Culvert (Three Lobed), just woozy instrumentals that sound like a class of sitar students detuning their instruments. But they’ve followed it up with Drone Trailer (DiCristina) and Barn Nova (Ecstatic Peace!), two albums that situate their spacey explorations within songs that sound like good old-fashioned classic rock. That is, if your idea of classic rock begins with Neil Young’s Zuma and ends with the side of Young’s American Stars ‘n Bars that has “Will to Love” on it, with a detour down John Bonham’s Boulevard of Heavy Beats. This Monday at the Empty Bottle they’ll play as a duo, so I’m betting things will be pretty loose. Locals A Tundra open and the show is free.