CHICAGO -- As Neutral Milk Hotel's Jeff Mangum stepped up to the mic in the dark, packed, sweaty club Lounge Ax, he took a step back, then forward again.

He seemed unsure, if not hesitant.

Finally, he moved toward the mic and stared with some awe at the size of the crowd. The crowd of several hundred, who had obviously come to build up a sweat and burn up the dance floor, waited for Mangum to say the word.

Then Mangum, in all his musical glory, began to strum his guitar, working his way ever so cautiously into "Oh Comely" off the new album, In the Aeroplane Over The Sea. Backed by a steady undercurrent of drone from a flugelhorn and bowed saw, the crowd stood perplexed, listening for the inspiration to dance or move to the beats.

And while Mangum's slightly overdone vocal on this sonically barren, danceless track failed to hook the audience at first, time would tell the true story of this night. That is, the story of a band that has chosen a path that demands more thought, less mosh.

As Mangum began to pick up steam, with his bandmates and other musicians taking their places on the cramped, foot-high stage, the Chicago crowd out on this Sunday night pricked up their ears. Their feet would soon follow.

When the first notes of "The King of Carrot Flowers Pts. Two & Three" sounded, a murmur of cheers rumbled through the audience. Mangum again paused to remark that halfway through their mini-tour opening for Superchunk, this was the first audience that had obviously been listening to Neutral Milk Hotel's new CD. "This is the first crowd on the tour that has heard any of these songs," he said. The band's new CD was released in February.

As the drone was replaced with a frenzy of accordion, horns and electric organ, those closest to the stage began to bounce with delight.

The band themselves took to moshing, almost hitting their heads on the aging acoustic padding of the low ceiling. But that's as wild as it got. Neutral Milk Hotel segued into "Two-Headed Boy" (RealAudio excerpt), and the words were carried away in the fuzz-fused current, swirling from Mangum in forcefully sung torrents.

With all of its strange instruments, there was no way the band was going to keep the audience on their toes. NMH's sepia-toned music doesn't really lend itself to a consistent mood, and that's the problem for anyone looking to generate a sweat at their show.

It's also what makes them so intriguing to see onstage.

NMH is rarely, if ever, poppy and often schizophrenic, moving from here to there in a more or less rhythmic manner. At times, the music holds together, but at others, it falls deliciously apart. And as the band lurches and veers from the beat path, it becomes harder for the audience to follow. Still, the crowd's attention was held during the softer songs, despite a palpable release of energy, even as Mangum belted out his stream-of-consciousness lyrics.

Some songs, such as the opener "Oh Comely" and the title track, are mostly

slow, quiet numbers with a heavy emphasis on Mangum's vocals and guitar

work. On these numbers, Mangum delivers his lyrics so forcefully as to

border on grating.

Others, such as "Two-Headed Boy" and the untitled instrumental track simply listed as "10" on the CD, exploded as bandmember Julian Koster moved to an electric bass, sometimes bowing it on the floor.

The actual lineup of the band was in constant flux during the performance. Sometimes the brass section filled out the left side of the stage on flugelhorn, trombone, trumpet and sax. Mangum stayed right of center stage. The organist was in the back left corner, facing the wall as if out of punishment. Koster bowed almost everything he played, not just the saw, but the banjo and the bass guitar as well. And the live arrangements adhered largely to those found on the CD, making for a musical masterpiece of an evening. [Tues., March 3, 1998, 9 a.m. PST]