The stage at Harris Concert Hall, Aspen's 500-seat gem with ideal acoustics, is never quite so full as it is for the annual concert by the Aspen Percussion Ensemble. Aside from the obvious -- snare drums, bass drums, timpani, xylophones, marimbas, vibraphones, chimes, tubular bells and cymbals -- racks of chinese gongs, tiny Tibetan cymbals, triangles of various sizes, tuned blocks, Indian tablas, a celesta, a piano, tables full of maracas, cowbells and other Latin instruments, all wait silently before the lights go down and the practiced hands of the musicians set up a glorious racket.

It's darned fun, is what it is. And the music is not just noise, it's something to chew on. Under the direction of Jonathan Haas, who once presented a concert for solo timpani in Carnegie Hall, the percussionists at Aspen come together once every summer for an evening that is always entertaining. Haas has a sense of theater that has in the past costumed the musicians as aliens, arrayed the stage with metal sculptures to be played as instruments, and played Philip Glass' music for the movie Khoyanisqaatsi while portions of it played on a screen in back of them.

One big theatrical moment this time -- a performance of Tongues, by the playwright Sam Shepard -- turned out to be the low point of an otherwise solid program. A series of dissociate monologues were stitched together for an actor to read while a percussionist interjected sounds from behind. It was painfully reminiscent of a bad 1950s beat-generation coffee house. But colorfully attired Latin dancers salsa-ing onstage for Rolando Morales-Matos' "Plena linda," which closed the concert, entered better into the spirit.

Joan Tower's 2003 composition for five percussionists, DNA, opened the concert. The structure mimics DNA, with four of the percussionists pairing off for internal duets while the fifth acts as a soloist, developing the rhythms they suggest. Tower's sensitivity to the sounds of the cymbals, castanets, tam tams and snare drums created some wonderful sonorities and the soloist's tuned blocks, tablas and tambourines added plenty of additional color.

Two of the compositions on this program are reprises of Robert Miller's Full Circle, a symphony for percussion, and Peter Schickele's Percussion Sonata No. 1, both commissioned for the first percussion ensemble concert in Harris Hall when it opened in 1996. This time they played only the relatively gentle slow movement, called The Secret Room, from Full Circle. It relies on piano, celesta and glockenspiel to carry melody and harmony, a refreshing change from the other, mostly rhythm-centric pieces. Schickele's piece keeps the harmonies simple, the melodies modal, and emphasizes jumpy rhythms.

The most complex piece on the program, and ultimately the most satisfying, was Tan Dun's Elegy: Snow in June. Subtitled "a concerto for cello and percussion," it gives the cello strident, angular lines and lets it join in with the drummers in loud, clattering sequences before finally resolving into a gorgeous Chinese-tinged melody in the final minutes. The final section was breathtaking, similar to some of the writing Dun did for Yo Yo Ma in his score for the movie Crouching Tiger, Hidden Dragon.

The piece was written in 1991, long before the movie score, and Dun's musical language was much more caustic and dissonant then. Cellist David Requiro lit into the music with a real flair for its colors and the percussionists played the complex rhythms with ease.