It goes without saying, but this time it bears pointing out: Great concerts are nothing like great albums. Great albums – of which Iceland’s internationally adored avant-garde diva Bjцrk has made at least three – often demand repeated plays and lengthy consideration before their pleasures truly reveal themselves.

Even albums showered with hosannas the day they surface – witness recent works from Arcade Fire and Radiohead – can still seem alien, impenetrable and confusing even after a half-dozen spins. Like all important art, their mysteries aren’t solved upon first glance. On the other hand, the greatness of a concert, by its very nature, is often based entirely on first impressions.

It’s a far more visceral than cerebral reaction: The stature of a show may grow in your mind as you contemplate it weeks later, but that on-the-spot rush is the convincer. If you didn’t feel yourself being thrilled as it was happening, it’s a good bet the show wasn’t as great as you might be kidding yourself into thinking it was.

All of which is my way of explaining this: A half-day since it ended, I still can’t make up my mind about Bjцrk’s performance Wednesday night at the Nokia Theatre in downtown L.A. I felt little on-the-spot-rush, to be honest, and yet I still have deep admiration for the talent on display. It’s proving to be that rare concert beast – a thinker, one that may later (or may never) add up to something more than mixed emotions.