Sigur Ros uniquely rocked Stage AE

PITTSBURGH -- Nobody sang along Thursday when Sigur Ros played a jam-packed Stage AE.

Oh, fans enjoyed themselves, it just would take an immense effort to learn the mix of Icelandic and self-invented ambient vocals that Jón Bór "Jónsi" Birgisson sings in so ethereally. His pretty voice is a one-of-a-kind instrument, scaling towering falsettos without sounding fragile.

The art-rock/post-rock trio played a two-set, career-spanning performance, for which just about every song featured Birgisson pulling a violin bow across his guitar's strings, making a haunting, cinematic sound. Only on a few quick bursts of aggression did it turn into a Jimmy Page, Hammer-of-the-Gods flurry.

Sigur Ros bassist Georg Holm and drummer/keyboardist Orri Páll Dýrason -- type their names into an iPhone to see if AutoCorrect explodes -- were masterful at patiently building up to moments of mesmerizing intensity. Especially Dyrason, whacking his drums with two mallets.

Sigur Ros didn't talk to fans, who had learned earlier in the day that the show had been moved indoors -- partially because the band wanted a darker backdrop for its dazzling light show; and also due to the threat of rain.

At the onset of like the 10th song, Dýrason acted frustrated with the sound as the show came to a screeching halt for a few confusing moments.

"Refund!" yelled a smart-aleck in the crowd.

A normal band would have apologized or joked about the situation, but Sigur Ros said nothing. At that point, after so much emotional intimacy and weightiness, it would have been weird if they did say anything.

Those lighting effects lived up to the hype. We've all seen laser beams at concerts, but Sigur Ros used what looked like a gunfire of laser bullets shooting out over the crowd.

Fans were focused and evidently knowledgeable about the songs with all those Icelandic titles and exotic accent marks.

"Ný Batterí" from Sigur Ros' 1999 album earned an extra ripple of recognition.

But without lyrical hooks or stage banter, I'll admit there were times I felt my thoughts wandering. You know, when you start thinking things like, "OK, what time do I need to set the alarm for tomorrow?" But Sigur Ros always snapped me back to attention and wonderment when they'd hit a passage of sheer intensity, with pounding drums and artful guitar and that elegant, hypnotic singing voice.