Part of making a living as a musician these days requires a continual juggling of social-media presence, touring and making merch available while trying to maintain an air of authenticity and integrity. This says nothing about mining the inspiration and energy needed in creating new material. Two decades in, and Colorado’s Yonder Mountain String Band appears to have all its balls happily and effectively in the air, which has resulted in a loyal fanbase positively responding to the band’s hustling. The group continues to expand its self-proclaimed “progressive bluegrass” beyond usual themes and sounds toward broader territories like reggae (“Grooving Away”), expressive shred (“Eat In Go Deaf, Eat Out Go Broke”) and stadium rock (“Fall Outta Line”). At heart, they’re a bluegrass band with Americana in the starting block. But just as the definition of what it means to be American is being re-shaped, so is Yonder Mountain String Band chipping away at convention.