It’s the economy, stupid. This notion has been taken to heart lately by musicians in particular. But with just two instruments and two people, you have a little more room to move. Vonnegut would recognize this as a nation of two, and here’s one that’s flying a don’t tread on me flag. Rock duo Jucifer originated in the heavy ’90s, juxtaposing beauty and anger — drenching audiences with waves of distorted guitar at top volume, Amber Valentine sings sweetly and sometimes hauntingly over Edgar Livengood’s ambitious and threatening drum lines. Having over a decade of touring under its belt, Jucifer’s new double album, L’Autrichienne, also branches into pop and blackgrass territories with veteran confidence.