The stars aligned in Ann Arbor for the first time in 50 years as founding composers of Ann Arbor's historic ONCE Festivals — Robert Ashley, Roger Reynolds, Gordon Mumma and Donald Scavarda — reunited for concerts and events showcasing their work.

"ONCE. THEN. Music + films from the ONCE Festivals," a sampling of what put Ann Arbor on the map of avant-garde music in the 1960s, was performed under the auspices of the University Musical Society by faculty artists of the University of Michigan School of Music, Theatre & Dance; the Creative Arts Orchestra; and the Digital Music Ensemble on Tuesday evening at U-M's Rackham Auditorium. The works were selected by the composers, and a piece by the late George Cacioppo, another ONCE Festival composer, was also on the program.

Flute and piccolo player Amy Porter and pianist John Ellis opened the concert with a shimmering performance of Reynolds' "Mosaic" (1962). The piece, in 12 sections, is rich with musical color and interplay between the instruments, exploring different forms of articulation (trills, key clicks, etc.). The work seemed remarkably fresh almost 50 years since its premiere, and a few cheers rang out from the nearly full house when Reynolds stood up during the applause.

Ashley then took the stage for a few words, taking a comic turn as he said, "I hope you like my music better than any of the other stuff you'll hear," drawing laughs and a few more cheers from the audience.

Director Mark Kirschenmann then led the Creative Arts Orchestra through a vibrant performance of Ashley's symphony, "in memoriam ... Crazy Horse" (1963). Group dynamics hold sway in this work, and the instrumental voices created a kaleidoscope of textures, with particularly luscious riffs from the harp in the opening. Laughter, vocal sounds and hand claps from the instrumentalists were part of the mix at times, adding an unexpected dimension to the highly dynamic work.

Mumma's "Large Size Mograph 1962" for piano was influenced by seismograph-recorded wave patterns of earthquakes and underground nuclear explosions. As Mumma wrote in a program note: "I was intrigued with the relationship similarities between the time-travel patterns of P and S waves and sound-reflection characteristics of musical performance spaces." Ellis gave a careful reading of the rather stark work, followed with Scavarda's "Groups for Piano" (1959), in which the composer explored how short a complete piece of music can be. Scavarda wrote in the program notes that "the piece created a storm of controversy at its premiere." Ellis successfully held the audience's interest as the work flashed by. Decades later it seems very uncontroversial.

The circular score of Ashley's quartet "in memoriam ... Esteban Gómez" (1963) allows performers a lot of freedom in the realization of the work. Carefully contoured with amplification and electronic manipulation by the Digital Music Ensemble, the often static musical gestures boosted by the extra amps ebbed and flowed with a sense of profound, underlying power. The mood of the audience seemed electrified by the performance as well.

Scavarda then took to the stage and thanked the audience "for having the courage to show up tonight." He talked about his work in creating film as a musical score "before color television." His interdisciplinary works "FilmSCORE for Two Pianists" (1962), "GREYS, A FilmSCORE" (1963) and "GREYS" (1963) experimented with abstract film, symbols, visual information and music performance. Pianists Michael Daugherty and Kristin Kuster performed "FilmSCORE for Two Pianists," interpreting symbols of moving discs of light from the inventive score projected above the stage. A silent screening of Scavarda's abstract film of colored orbs, "GREYS, A FilmSCORE" was then shown. It was repeated as "GREYS," with a stereo electronic music track by Mumma.

As ethereally beautiful as the celestial patterns on which the score it is based, George Cacioppo's "Cassiopeia" (1962) also offers the performer a variety of options. Daugherty gave a sparkling, dynamic and rather brief performance at the piano of the exquisite work.

Mumma then reflected on his composition "Sinfonia" (1958-60) for 12 instruments and magnetic tape, saying the four movements were more like four scenes with a sound theater quality. The electronic music in the third movement contrasted with the more classical parameters of Mumma's work for the instruments. It spun a new perspective on the piece when the instruments re-entered without the tape.

Scavarda's pioneering use of multiphonics (more than one note played at a time) in "Matrix for Clarinetist" (1962) was then given a highly sensitive, virtuosic performance by Daniel Gilbert.

Completing the program was Reynolds' "A Portrait of Vanzetti" (1962-63) for narrator, chamber ensemble and electro-acoustic sound. Combining instrumental and electronic music, Reynolds took the text from the letters of anarchist Bartolomeo Vanzetti. In his remarks before the performance, Reynolds said he wrote the work in response to the destruction he witnessed after World War II in Germany. George Shirley gave a riveting narration of the text, which sailed above the evocative composition.

The dramatic ending of the piece closed out this excellent retrospective concert on an intense note. The audience rose in a standing ovation as the composers took to the stage, applauding their work that will be forever linked to a brilliantly creative period of time in Ann Arbor.

For a complete listing of events associated with the 50th anniversary celebration of Ann Arbor's ONCE Festival, which continues through Saturday, visit the ONCE Festival website.