Beats by Xenakis, at the Aspen Music Festival

You’re invited to lie down on the stage of Harris Concert Hall on Monday night for a musical experience that, probably, no other audience has had.

In its annual recital, the Aspen Music Festival and School’s Percussion Ensemble will perform “Persephassa,” by the Greek composer Iannis Xenakis. The avant-garde pioneer also was a music theorist, mathematician and architect. In this rarely performed piece, which debuted in 1969, Xenakis combined his expertise in science and music.

Due to technological limitations, it’s never been performed exactly as Xenakis intended, Percussion Ensemble director Jonathan Haas said. He’s charging his students with doing so with the help of a digital click track.

Xenakis included in the composition a diagram for how to spatially configure the stage, with six percussionists arranged in a hexagon and the audience lying down in the center. Audience members — as many as can fit — will join the musicians on-stage for the Aspen performance, with some padding provided (“yoga mats and inflatable rafts and sleeping bags,” in Haas’ words) for comfort.

“We have stage seating (at the Aspen Music Festival), but I don’t think we’ve ever had stage lying down,” Haas said.

The idea is for an audience to recline and listen with eyes closed as sound from the ensemble moves across it.

“The way it’s designed, the sound is at times spinning around; sometimes it’s going at diagonals,” Haas said. “You’re lying there, and you’re literally hearing things swirling around.”

The piece, as it grows in intensity, has its six percussionists split off into different time signatures, a complex compositional quirk that has made it impossible for musicians to play it faithfully. Mathematically, if it’s played the way it’s composed, the times eventually sync up again. Haas is challenging his students to pull off the work precisely through the use of a special click track that he had engineered in New York. Students will hear the click track in earbuds, wearing shooting earmuffs on top to cancel out sound from the rest of the ensemble and keep it from throwing them off their time.

Haas saw the piece performed at New York’s Lincoln Center in 1976 as a Juilliard School student and hoped to find a way on day to play it strictly as Xenakis wrote it. Now, he thinks he’s found a solution.

“The technology didn’t exist to play this piece the way that the composer intended,” he said. “We’re going to play it exactly the way he intended. … The way Xenakis composed it, it all works out. But humans can’t do it all by themselves.”

“Persephassa” itself is a riotous, at times overpowering 22-minute piece of music filled with waves of drumrolls and directional explosions of sound, including flourishes of sirens and clicking stones. (Earplugs will be available Monday.)

“All of these technological setup things are interesting, but as a piece of music it’s a tour de force,” Haas said. “It’s a workout.”

A workout indeed. On a recent Sunday night, six student percussionists surrounded Haas in a rehearsal room on the Aspen Music School campus amid what looked — to this reporter’s untrained eye — like a chaotic jumble of timpani, wood, gongs, maracas and metal sheets. The configuration formed something like one giant drum kit as the students worked through the intricate dynamics of the composition.

During one particularly dense section that calls for rapid and sustained drumrolls from the players, Haas reminded his students, “Xenakis is telling us exactly how many strokes should be in the rolls.”

“Well, he’s crazy,” shot back one exhausted student.

“Right,” Haas said. “He’s crazy. But no matter.”

Haas won’t be on stage for the Xenakis performance Monday, as the click track guides the musicians and the stage is filled with recumbent listeners. But he shook feverishly as he goaded his ensemble through one stormy section of “Persephassa” in rehearsal.

“If I looked like I was having a grand mal seizure, this is because you need to make those clouds like what rolls in here at 4 o’clock — very thick, very dense,” he said, referring to this summer’s violent thunderstorms in the Castle Creek Valley.

The Xenakis piece will conclude a program with an exotic flair inspired by the summer season’s “Dreams of Travel” theme, showcasing musicians from the school’s 19-student percussion program.

“We’re going to take people on a journey like no other,” Haas said.

It will open with a percussion arrangement of Philip Glass’ “Train to Sao Paolo” from the film “Powaqqatsi,” followed by a movement from David Byrne’s “The Forest,” which includes Aramaic chanting (in an arrangement that Haas put together from a score Byrne neglected in milk crates in his New York City apartment).

After those short pieces, the ensemble will perform Christopher Rouse’s evocation of Hawaiian mythology, “Ku-Ka Ilimoku.” Haas and his student ensemble performed the piece once before, in 1986 at the Wheeler Opera House, with a misguided use of a smoke machine to evoke the Hawaiian god of war (it set off the fire alarms).

“Everyone thought that the alarms were part of the piece,” Haas laughed.

Robert McDuffie, an internationally renowned violinist and Aspen favorite, will then join the ensemble to perform Lou Harrison’s Concerto for Violin and Percussion. The piece pairs the violin with beats on tin cans, brake drums, metal pipes and other nontraditional instruments.

“To have Bobby do something like this with us is an extraordinary opportunity for my students,” Haas said.

The recital also will include Derek Tywoniuk, winner of the Aspen Music Festival’s percussion solo competition, performing Franco Donatoni’s “Omar” on vibraphone.

atravers@aspentimes.com