If Yonder Mountain String Band’s fourth studio album and self-titled debut for Vanguard Records sounds a little different, well, it should. It marks the first time the burgeoning progressive string band has worked with a stellar rock producer—Tom Rothrock (Foo Fighters, Elliott Smith, Beck and James Blunt—it’s the first time they’ve added a little drums to their mix of banjo/bass/mandolin/guitar and it’s the first time they’ve written almost an entire album spontaneously. Yonder Mountain String Band catches them transitioning into more folk and rock territories and most certainly and ceremoniously exploring different sounds and ways of songwriting.

Previously, guitarist Adam Aijala, mandolinist Jeff Austin, banjo player Dave Johnston and bassist Ben Kaufmann would each show up to the studio with their own songs, or songs that had already been worked up on the road. But with Rothrock behind the boards, they sat around and came up with songs that stirred the band’s creative juices in a new way. “It definitely was the challenge that was ready to be taken on,” says Austin. “For me, it was a very necessary step that the band had to take, just because we’ve always been about letting ourselves experiment to the full width of the spectrum. It was a part of us that was just dying to come out.”

Under Rothrock’s leadership, Aijala added electric guitar to the album, while Austin, milked an old ‘70s amplifier for feedback with an acoustic mandolin. Ambient noise accompanies the disc-ending “Wind’s On Fire.” The cinematic instrumental “Midwest Gospel Radio” was born out of Rothrock’s request for a spiritual number.  Says Aijala, “Tom’s input certainly gave the songs a new and interesting feel.”

On the upbeat, rousing, first single “How ‘Bout You?” and “Classic Situation,” the band also brought into the fold Elvis Costello drummer Pete Thomas, who changed the sensibility of the record, says Ben.  “All of a sudden, our perspective got a little broader. His drumming shows up fundamentally and very subtly in places throughout the record. I’ll leave that up to the listener to find these.  We ended up with an album that’s got rippin’ bluegrass on it, but approached in a non-traditional way, which really appeals to me because we are not a traditional band.  It’s always been forward-thinking and this is the first time we’ve captured that in the studio."

As a result, the always progressive Yonder Mountain continues to close the gap between bluegrass and rock: With its dueling electric guitar/banjo solo section, “How ‘Bout You?” has the goods to turn people on to a new way of thinking about how a banjo can be played. “There are places where the banjo and the mandolin become rock instruments,” says Kaufmann. “Angel,” meanwhile, could be dubbed “hard-folk” “That’s a song where we draw from personal influences that bridge—for us—our love of heavier rock music, with lyrical imagery that’s clearly traditional,” Kaufmann continues. “There’s a fiddle in the solo section, but it’s clearly channeling the spirits of the rock guitar gods.”

Fusing traditional elements and modern techniques, the disc’s leadoff cut, “Sidewalk Stars,” appropriately and perfectly captures the spirit of Yonder Mountain on this album.

A few of the tracks were worked up live, and a few come from outside sources. “I Ain’t Been Myself in Years” was written by band friend Benny Galloway, and “East Nashville Easter” was penned by Austin and lauded singer/songwriter Todd Snider. And it’s in songs like the latter where the band’s experimentations make even more sense.

Twisting and bending their sound with a rock producer was a natural next step for a group of guys who actually grew up on rock music. Comprised of Colorado transplants that grew up in the Midwest or Northeast, none of the band members had backgrounds in bluegrass music, but rather discovered it through old and new records and fellow musicians during college.