Twenty-seven members are still outnumbered and outflanked by their equipment, but hardly overshadowed.

Tonight at 8 in Theatre 1, the USF Percussion Ensemble will tap out and breathe life into hundreds of their musical counterparts.

“For a lot of people the first time hearing this concert, they’re going to hear chaos,” said Lee Hinkle, a senior and four-year veteran of the USF Percussion Ensemble.

The spring concert involves the ensemble’s 15 percussionists plus various guest performers: eight brass players, a pianist, an organist and two electronic-keyboard players.

Hinkle said playing percussion involves more than just keeping time on a set of drums, and the group is known for playing a culturally and technically diverse avant-garde repertoire.

“(It’s) not mainstream,” Hinkle said. “Even within art music there are certain stereotypical things that get written for percussion … like a rock drum beat. Composers will write … repetitive rhythms that, to us, get really boring. They can be written in interesting ways but so often they don’t.”

One piece the ensemble will perform is “Ecuatorial,” a fervent fusion of brass, unanticipated tempo and eerie, otherworld sounds by early 20th-century composer Edward Varése.

Hinkle is also a student of opera and sings a rich, reverberating Spanish translation of ancient Mayan religious incantations as the piece’s featured vocalist. Through months of practice, his regard for “Ecuatorial” morphed from dislike to appreciation.

“The first time you listen to it, (it) may not make sense or you may not even like it,” Hinkle said. “It’s a bizarre piece. It’s not the kind of music you’re used to hearing.”

From the “warm, pretty sound” of the marimba to the “sharp, articulate” ring of the xylophone, Hinkle said audiences will gain a unique appreciation of how simple sounds can come together to create new music.

“A single ‘ding’ on a triangle can be a beautiful sound in and of itself,” he said. “It doesn’t have to be a tonal melody like you hear in every pop song every day. It gives you the opportunity to experience new things aurally that you’ve never experienced before.

“There will (be) literally hundreds of different instruments on the stage and we have to know how to play all of them.”

Music majors are expected to put in several hours a day practicing for classes, ensembles, orchestras and personal lessons as well as multiple end-of-year recitals for seniors.

Members of the percussion ensemble class practice an average of at least 20-30 hours a week outside of their rehearsals together, and preparation began a year ago. Music education freshman Ian Kerr was still in high school when he auditioned for USF’s School of Music last February.

“(You) come to ensemble and it’s a given that you know your stuff,” Kerr said.

Freshmen are half of this year’s class, but Kerr said he is driven to learn the music one senior deemed “ridiculously hard,” because they have so much fun doing it.

“We’re learning probably at a faster pace, because we’ve just been exposed to so much in a short time,” Kerr said.

“The (older) guys are really awesome because they help us a whole lot. They’re there for us. They want to help us. Any question we have, it’s almost like we have another professor here.

“I really want to study and work and practice as much as possible to catch up with those guys, just to be on everyone else’s level.”

To get there, Kerr said he learns not just the notes but also about the composer’s life — the thoughts, emotions or personal events he or she might have experienced when writing the music. Integrating what he learned from visits with two of the program’s featured composers, USF alumnus Paul Bissell and Korean musician Lee Gui Sook, also helped grasp “the feeling of music, which is more important.”

Aside from the marimba, shakers, tom-toms and wind chimes, Kerr plays the water glasses for the ensemble — altering and marking water levels with a Sharpie to keep track of the pitch. Sound vibrates when he rubs a wet finger against the top of a glass.

Percussionists specialize in feeling music by striking chords with every instrument they lay their hands on.

Music performance senior Grant Beiner has played the marimba since high school.”As a percussionist, that’s not the only instrument I play,” he said. “We’re required to pretty much know how to play everything.”

With about 500 instruments stashed in their professor’s office and several different musical pieces to practice for senior recitals and graduate school auditions, students like Beiner and Hinkle work six to 12 hours a day to become fluent with multiple instruments.

A piece like Japanese composer Maki Ishii’s “Marimbastück,” where the notes seem to scatter across the page, would leave the novice musician hanging.

“It’s all about free time,” Beiner said. “(None) of it is based on a beat. So it takes a lot more creativity. It is (chaos), but it does have form to it,” he said. “It’s not just a whole bunch of random stuff flying on a page.”

There are measures without specific musical notes or direction, in which the composer only suggests a range of notes or beat to follow. Hands busy, Beiner’s trio tunes in to how they all are playing and conduct with their heads to maintain the unwritten rhythm.

“We give head nods and we work on the speed,” Beiner said. “So we’ll keep it consistent when we play it.”

The result yields entertainment for the eyes and ears. During one practice, Beiner sneezed and a fellow musician struck his note.

You just have to close your eyes and feel the piece, Beiner said.

“Feel the piece and grow with it,” said Robert McCormick, who has taught percussion for 30 years at USF and is a world-renowned musician.

“Bob (McCormick) is hilarious,” Kerr said. “He has a great sense of humor. He has so much zest … sometimes when he’s explaining to us how to play a part he starts conducting and he starts dancing.”

McCormick hops from one foot to the other, tapping out complex musical parts with alternating-time signatures in order to help his students understand the rhythm.

“He’s so into it,” Kerr laughed in explanation. “It’s a lot easier to rehearse when you’re not gritting your teeth.”

“Music is not a competition. It’s a creative art to me. It’s not like sports (where) you are the winner. (The students) have to be creative enough based on the instruction that I give them to make something happen musically. The group of students that I have now is as dedicated if not the most dedicated I’ve ever had here,” McCormick said. “So we are definitely drawing outstanding percussionists to USF right now. They work very, very hard. It’s not only listening to what (you are) doing but to how others are playing around you and how you fit into that.”

This same uplifting attitude seems to translate into a synergy that drives the group through early morning rehearsals.

“(You) have to go into this knowing (you’re) going to hear things (you’ve) never heard before,” Hinkle said. “Be as open-minded about it as you can, because there will be things in this concert that I would venture to say 99 percent of the people (who go) will not like.

“Try and keep an open mind and let your ears do the thinking,” Hinkle said. “It’s like the first time you drink coffee: It’s probably going to taste pretty bad.”