The wind was picking up as Parachutes and Sigur Rós played the final show of this year’s summer season at Red Rocks Ampitheater.

An autumn chill settled on the venue as the first band took the stage on Sept. 27.

Parachutes opened the evening before a sparse crowd, but the stands slowly filled with indie-scene fans, young adults and the occasional preteen with parents in tow. The soft-spoken band seemed to be providing background music instead of commanding the attention of the audience.

People mingled and talked during Parachutes’ quiet and modest set that offered soft vocals and tender string instruments. The guitar player went so far as to sit onstage. Although Parachutes didn’t play poorly, the band’s sound was simply too humble to grab the attention of anyone in the sparsely filled venue.

After a long set change, the lights were killed and a gentle melody played on a piano filled the air. As the delicate chords stretched out into the dark, a handful of small flickering lights outlined the perimeter of the Sigur Rós stage set-up. Behind the audience several random, pale, inflated globes with black sashes trailed in the wind.

Thus, Sigur Rós began what would turn out to be a profound performance. Playing tracks mostly from its new album, Meo suo i eyrum vio spilum endalaust (with a buzz in our ears we play endlessly), the band delivered fragile piano, strings, percussion and the iconic, piercing falsetto voice of Jón CBór Birgisson. As one song seeped into the next, the audience remained seated, lulled and entranced by the music of Sigur Rós.

Birgisson asked in broken English for the crowd to join him in singing. Many laughed assuming this was a joke because not many can follow the high notes or Icelandic language of the band.

Then, Birgission asked the audience to stand, warm up and clap along to the first single of the band’s new album, “Gobbledigook.” Other band members with drums around their necks took the stage to add the enhanced percussion for this song, and rainbow colors illuminated different stage areas as the joyful and carefree song persuaded the crowd to dance and clap.

The result was akin to a childlike wonder sweeping through the stands. Sigur Rós played quietly enough so that many people remained seated and mesmerized. Even though Birgission sang mostly in Icelandic or in what seemed like a gibberish of languages, his truly otherworldly voice built up and descended into notes so ethereal that the specific meaning of his words did not matter. In this way, Sigur Rós pulled the audience into introspection under the dark, autumn sky.