NEW YORK — As fans ambled into a tiny chapel at Riverside Church on Tuesday night, security guards kept reassuring them they were in the right place. Roughly 200 fans, who had scored tickets through the Icelandic singer's Web site, were at the historic Manhattan church for an exclusive first taste of Björk's upcoming album, Vespertine. They filed into the neo-gothic chapel to the strange, looping circus hymn of an oversized, transparent Porter music box playing its tune over and over and over. The chapel was adorned simply, with flowers and a few candlesticks. Harpist Zeena Parkins and experimental sound collagists Matmos were crammed into opposite sides of a stage assembled in the nave of the church, with a 12-woman choir between them.

After the other musicians had taken the stage, Björk demurely walked to the nave in a simple white dress, said nothing, slid off her shoes and stepped past the microphone. Underscoring the intimacy of the venue, she sang the opening verses of the somber "Unravel," from her 1997 album, Homogenic, without a microphone as she walked barefoot through the chapel. Fans in aisle seats were clearly awestruck as she brushed past them.

"Undo," the first new song of the night, Björk's voice soared over ethereal rings emanating from Matmos' Macintosh computer. The electronic duo — who collaborated with Björk on Vespertine (due August 28) — slipped subtle bells and tones into the mix without overwhelming Perkins' delicate strumming.

Perkins switched to organ for the next song, "All Is Full of Love," the final track from Homogenic, and the last non-Vespertine song of the night.

For the delicate, playful and sadly sweet new material that followed, Björk — who performed two identical 45-minute sets at the church — stretched her voice over layers of warm, acoustic instrumentation and Matmos' staccato blips and snaps. Some textures called to mind Radiohead's electronic opus Kid A. The Asian-inflected "Pagan Poetry" evolved into a gospel number, as the singer and her choir engaged in a dynamic call-and-response refrain. "Cocoon" was an emotional highpoint of the night, with Björk alternately singing and whispering about the most intimate of human behaviors in blush-inducing detail.

For "Aurora," Matmos' Martin Schmidt stepped out from behind the computer to crush out rhythms using his feet and a box of Styrofoam, emulating the sound of boots trekking through snow.

Themes of love and sacrifice resurfaced on "Palmstroke," in which Björk sang, "I give myself up ... I'm eternally yours" as Perkins' harp accompaniment soared to an intense climax.

Throughout the show, Björk alternated between singing naturally and using a microphone. Between songs, she remained tight-lipped; her only words were to thank the audience for coming. She seemed most at ease during the night's final song, "It's Not Up to You." As the choir chanted the hooky chorus, Björk danced joyfully in front of the audience. It was a stirring finale and a signal to her fans that the singer is back in a peaceful place after the much-publicized trauma she endured while filming "Dancer in the Dark" (see "Bjork Says New Record Allowed Her To Clear Her Head").

The setlist for Björk's May 22 shows at Riverside Church:

  • "Unravel"
  • "Undo"
  • "All Is Full of Love"
  • "Pagan Poetry"
  • "Cocoon"
  • "Aurora"
  • "Palmstroke"
  • "It's Not Up to You"