TORTOISE

IT would be simple to slap a reactionary label on Tortoise to explain the music the band creates, but the Chicagoans were making avant-rock anti-pop long before Britney ever gripped a mike.

At Irving Plaza Thursday, Tortoise created a sonic-scape of space-age lounge music with vibraphone, marimba, bass, guitar and polyrhythmic percussion attacks.

It was an all-instrumental program that owed a giant debt to the Grateful Dead, old New Age noodler Tangerine Dream and jazz/rock fusionists Herbie Hancock, Stanley Clarke and Chick Corea. None of the tunes rendered during the two-hour, one-long-song concert ever approached the unusual vision of any of the band’s influences.

The music Tortoise shells out is totally anti-Elvis – no hooks, no vocals, no fun. There wasn’t even a thank you or a peep of chit-chat that might have humanized the band. It was, at best, music suited to play in the background of a party or in a film, with melodic mood, to further the plot.

The band was most successful when its jams were directed away from traditional jazz/rock and toward more elemental native rhythms that were brightened and given structure by instruments such as the marimba.

The band’s fans were often the harshest judges – the average wide-mouth, dropped-jaw yawn lasted six seconds. Unfortunately, the concert lasted two hours.

While the audience clapped warmly and politely afterward, it wasn’t the usual thunder you’d expect from a sold-out concert.

There were few midconcert patron departures, but in the quiet, quick interlude between the last composition and the Tortoise encore, there was a mass exodus, as at least a third of the house ran like hares from an opened hutch.