USC students and alumni perform at Union Station

The conductorless orchestra filled the station’s historic ticketing hall for a pay-what-you-can presentation of classical music.

Kaleidoscope Chamber Orchestra, the first and only conductorless orchestra in Los Angeles, packed the historic ticketing area of Union Station Friday for a performance of Charles Peck’s “Mosaic” followed by Beethoven’s “Pastoral” Symphony (No. 6). The concert, which featured a pay-what-you-can donation table rather than the traditional ticket booth, was filled to standing-room-only by 9:40 p.m., twenty minutes ahead of its 10 p.m. start.

The ensemble features three USC alumni and twelve current students — Roberta Yee, Catherine Baker, Robert Walker, Rachel Van Amburgh, Sérgio Coelho, Elizabeth Kosko, Brendan White, Mann-Wen Lo, Alex Granger, Chiai Tajima, Tommy Dougherty, Javier Iglesias, Juliette Herlin, Levi Jones and William Wasson.

The crowd was mixed with both orchestra devotees and curious passers-by bumping elbows before the performance began — a success, per the orchestra’s self-proclaimed goal: “We want everyone in Los Angeles to have the opportunity to experience great classical music in person by a professional orchestra.” Every aspect of the show was coordinated to make that happen.

When the concert began, the musicians arranged themselves near the center of the room, with seats on all four sides. They stood up, so that attendees could watch their every interaction.

To the crowd’s uncustomary applause between the movements of Beethoven, the concert program offered a warm-hearted response: “When someone claps at a ‘less traditional’ time, it lets us know there’s someone new to classical music or who is hearing the piece for the first time, which is a wonderful thing!”

By accepting donations rather than selling tickets, Kaleidoscope drew listeners who may have shied away from other professional orchestras due to steep ticket prices and a stuffy concert atmosphere.

What stood out on Friday was that the musicians in Kaleidoscope were clearly having fun. Without a conductor, entrances are coordinated through furtive glances and nudges, well-matched by the rambunctious musical selections.

American composer Peck’s new work “Mosaic” comfortably shared the stage with Beethoven. The piece, a single six-minute movement, attempts to use music to replicate the aesthetic experience of viewing a handcrafted mosaic, first peering closely at the constituent materials and their individual forms, and then zooming out to take a holistic view of the composite image.

Peck has translated the medium into music with grace and creativity. The composer builds and programs his own electronic instruments; though none are used in “Mosaic,” he mixes diverse shades on the orchestral palette with technological precision and clarity.

At the piece’s opening, muted, scraping strings suggest the mosaic artist as she combs the beach or forest in search of raw materials. Whimsical percussion interjections evoke their diverse forms: a rusted bolt, a shard of plastic.

The melodies elongate and coalesce as the mosaic is put together, building toward a false ending which really marks the beginning of the zoom-out. Here, a xylophone bubbles around intertwined woodwinds in a captivating evocation of some subsurface scene, perhaps the forge of Prometheus or a hydrothermal vent in the Marianas.

A rich brass section cements the final section of “Mosaic,” a chorale of cosmic intensity that radiates through the orchestra before giving way to a subdued, twinkling starscape of woodwinds and high strings. The composition is stellar, and the performance left little to criticize.

The orchestra’s rendition of Beethoven’s “Sixth” was spirited and joyful. The piece, meant to represent a village scene in the early-19th century German countryside, is full of playful references to country song and dance. Kaleidoscope dashed alongside each. And in the fourth movement, which represents a thunderstorm, the performers did not relinquish the boisterous optimism that defines the symphony as a whole. Instead, they bopped their way through to the piece’s cheerful finish.

Even when the performance paused, the orchestra brandished no clear leader. Between the two pieces, a violinist emerged from among the spruce to address the audience, then disappeared back into the fray to play his part the next piece. Kaleidoscope’s members avow that “a democratic process within the orchestra will improve the quality of the performance.” Indeed, neither piece sounded strained nor conflicted; it was evident on Friday that Kaleidoscope’s musicians are dedicated to the orchestra’s shared vision.

Its October series will feature new music by Jee Seo, West Coast premieres of pieces by Saad Haddad and Julia Adolphe and Leoš Janácek’s “Mládí.”

The original version of this article said that three alumni and 12 current students performed. Benjamin Mitchell, Michael Basak, Eric Lea and Michale Matsuno also performed, making the total five alumni and 14 current students. The Daily Trojan regrets the error.