Yonder Mountain String Band perform “Annalee” at Second Story Garage in Boulder, Colorado.

Yonder Mountain String Band is one of the Big Three bands from Colorado that followed the state’s progressive bluegrass tradition to years of touring and national recognition. Along with Leftover Salmon and The String Cheese Incident, YMSB has expanded the boundaries of bluegrass-based music, and it gets at least part of the credit for a proliferation of custom-named music genres that end in “-grass.”

The band recently announced a four-night New Year’s Eve run at the Boulder Theater. Yonder Mountain is the rare kind of group that can pack a venue such as the Boulder Theater four nights in a row. The run will cap a year that saw the departure of a founding member, mandolinist Jeff Austin, and something like a rebirth for the band. It’s been touring with regular guests Jake Jolliff on mandolin and Allie Kral on fiddle, and the band says the new dynamic is really working. Jolliff and Kral even have joined the band in recording new material.

When Yonder Mountain came to the Garage last month, they brought along Jolliff and Kral, and also were preparing to headline both nights of the Kinfolk Festival at Planet Bluegrass in Lyons.

The band played “Landfall,” “Annalee” and “Black Sheep” for us, then had an enthusiastic chat with Quentin that included a unique moment in interview history.

What they brought us: They found an unfinished bottle of Bulleit Bourbon and autographed it.

Sign up. Don’t miss out! Sign up for the Second Story Garage newsletter to keep up with local music news — show announcements, ticket sales information, previews, interviews and even an opportunity to sit in on a Second Story recording session. Sign up here.