In 2006, the psych-folk collective Espers played under a blanket of faux constellations and comets at Fels Planetarium in Philadelphia.

The setting was quite appropriate for a Philly-based sextet whose sound resonates with intergalactic drones, ’60s British folk music and a metaphysical essence, and whose name refers to an individual with telepathy or other paranormal powers. Big Sur, where Espers plays Fernwood Friday night, is an equally appropriate venue for the band to let its freak flags fly.

Espers formed about eight years ago but really began to blossom in ’06 when the founding trio – Greg Weeks, Meg Baird and Brooke Sietinsons – added cellist Helena Espvall, drummer Otto Hauser and bass player Chris Smith to the lineup and moved to its current Drag City record label.

With rich, orchestral-like arrangements, Espers’ music is infectiously intriguing. Heavy amplification is contrasted with increments of immaculate, more conventional folk. You never know what direction the songs are going, but you always want to see where they end up. Each is a small demonstration of freedom, packed with a variety of musical ideas and dominated by abounding harmonies with a cockney, Fairport Convention vibrato.

Recently, Espers’ captivating songwriting caught the attention of Marianne Faithfull. The renowned singer-songwriter covered “Children of Stone” on her album, Easy Come, Easy Go.

“The songwriters in the band write frameworks and eventually lyrics, then the band as a whole adds to the framework until it takes on a more cohesive identity versus a personal identity,” Weeks says from his mother’s home in Rochester, New York.

Espers’ new album, III, is an infinite voyage into a cluttered land of sun-soaked instrumentals and innovation, a clear departure from the band’s previous, more ominous albums.

On the opening song, “I Can’t See Clear,” Meg Baird’s voice flickers with the vitality of The Cranberries’ Dolores O’Riordan as piercing arpeggios of Weeks’ electrified lead hover over the strums of an acoustic guitar.

“Colony” begins with the deep moans of a cello before giving way to an abundance of percussion and whirlwind of melody as engrossing as a Philip K. Dick short story.

Elsewhere, Espers’ lyrics can be tricky to pick apart, but allusions to nature and the perpetual destruction of the environment are everpresent.

“Nature is on the minds of most people who care about the longevity of the planet as we know it,” Weeks says. “We’re at a real tipping point here, and things are not being addressed with the speed and urgency required to keep us all from a dramatic and horrific turn of events. I think as a band we all want nature to start encroaching on man for a change.”

Though music is just as important to Weeks as the environment, he is somewhat leery about his future as a musician and discouraged about the economy’s effect on all musicians.

“The financial component worsens for musicians, which means less money and less ability to tour and play live – and less time for writing and rehearsing,” he says. “It would be less depressing if the role of music was changing [and diminishing] in people’s lives, but music remains as important as ever and it’s the worth of musicians that has degraded in many people’s minds, not to mention the quality of recorded music.”

Gifted folk singer Mariee Sioux, with an affinity to Mother Nature equal to Weeks’ – and a voice as sweet as sugar – also plays, as does Jeffertitti’s Nile.

ESPERS plays 9pm Friday, Dec. 11, at Fernwood, Highway 1, Big Sur. $15. 667-2422.