Colorado’s Yonder Mountain String Band has been doing it right through the grassroots grind-big festival bills, theatre sell-outs, and their own indie label. Apparently, though, they don’t feel like resting on their laurels. The quartet, known for high-energy jam grass, was born out of the Boulder area’s fruitful experimental bluegrass breeding ground, which has spawned new traditionals like Tim O’Brien’s Hot Rize and more recently Leftover Salmon. But for their latest eponymous effort they came down from the mountain and inked a deal with New York City’s Vanguard Records.

Helping Yonder with their Vanguard debut was producer Tom Rothrock, known for his work with the Foo Fighters and most recently mega-hailed Brit crooner James Blunt. In some places he’s the obvious catalyst for experimentation, case in point when he adds out-of-place reverb to the intro of the ripping Scruggs-style instrumental “Fastball.”

Elsewhere the collaboration meets more of a successful middle ground with the eerie Beatles-esque feel of the disc opener “Sidewalk Stars” and country rockers like “East Nashville Easter,” which mando picker/main vocalist Jeff Austin penned with Todd Snider, and the slide-heavy “Angel,” which concludes with a bursting psychedelic fiddle solo from stalwart Darol Anger. There is also a play for the CMT crowd with a few leanings in the realm of song-friendly Nashville pop: the catchy chorus harmonies of “How ‘Bout You?” and the ageless themes of love lost in “Classic Situation.” Tunes like this will make the band’s small scale Grateful Dead-style fan base cry blasphemy. But with its overall Americana variation the album should be Yonder Mountain’s ticket out of the jam band niche and into the pool of contemporary mainstays.