Master of the Mutable, in an Idiom All His Own

On a recent Sunday, in the home stretch of a concert at Roulette, a new-music institution in SoHo, Henry Threadgill shut his eyes and flashed an enigmatic smile. His longtime ensemble, Zooid, was nearing the end of a labyrinthine, nearly hourlong world premiere, and the atmosphere in the room packed beyond capacity, with people crowded in the aisles had become humid and heady. Mr. Threadgill swayed to the musics layered pulse before picking up his alto saxophone. Then, as if cued by a secret signal, he and his musicians landed together on a sharp, culminating blare. There was a moment of startled silence before an eruption of applause.

Mr. Threadgill, 65, has long been one of the most thrillingly elusive composers in and around the jazz idiom: a sly maestro of unconventional timbres, bristling counterpoint and tough but slippery rhythms. His output, like that of his fellow multi-reedists Anthony Braxton and Roscoe Mitchell, can veer toward contemporary classical territory, though it rarely settles there.

Henry is very fluent and open to the language of music, said Meredith Monk, a composer of similarly elastic sensibilities. Michael Lipsey, a member of the Talujon Percussion Quartet, which has performed with Mr. Threadgill and with Steve Reich, put it this way: Hes an amazing jazz musician, and at the same time, when you listen to his writing, it could sound like one of the American masters.