Opera is not the sort of art form that lends itself to easy experimentation. Typically, you need sets, costumes, an orchestra - not to mention singers who are usually booked 3-4 years in advance. So, nine years ago, City Opera hit upon the idea of giving American composers the chance to have their works heard in a workshop format, using the full City Opera orchestra and professional singers from their regular roster, as opposed to synthesizers and amateur friends. They called it: VOX.

Now in its tenth year, VOX is still going strong and has produced several notable American operas, including Richard Danielpour and Toni Morrison's Margaret Garner, which played at City Opera this past season to sold-out houses. Clearly, this is a win-win situation for all concerned.

VOX had it's most recent installment this past weekend at NYU's Skirball Center. Tickets were free, and easy to get through the advance reservation system (though I think most standbys managed to get in as well.) The theater, which sat 850, felt intimate yet formal. Each composer was allotted half-an-hour to present an excerpt of their work in concert format; many felt finished enough to stage. Without the benefit of an orchestra pit, all the singers were mic'd: a necessary and reasonable compromise.

Unfortunately, I was only able to attend on Sunday, but managed to hear representative performances of four distinct American voices. Scott Davenport Richards' Charlie Crosses the Nation tells the story of an Army big band playing the front lines during WWII. The music is written in an unqualified jazz idiom, sounding more like musical theater than opera but thoroughly satisfying. Richards didn't pull any punches on his libretto, turning the old Army acronym "SNAFU" ("Situation Normal All Fucked Up") into a rousing ensemble number.

Less successful was Alice Shields' Criseyde, recounting the story of Troilus and Cressida as told by Chaucer. The music is a strange blend of early Wagner, Britten, and North Indian raga while the subject matter (not to mention the use of Middle English in the libretto) felt completely divorced from modern reality. Not exactly an easy sell.

After an intermission, the performers returned with Justine Chen's gripping Jeanne, based on the life of Joan of Arc. Chen's music is dark, complex, even angry as it recounted the trials of Joan through the words of her captors. Particularly striking was Bishop Cauchon, who struggles with the possibility that the girl he's sending to the stake might actually be God's handmaiden. His aria (sung by Kevin Burdette) had the same wrenching impact as "Batter My Heart" from John Adams' Doctor Atomic, which I heard earlier this year in Chicago.

David T. Little's Soldier Songs is not an opera, but a cycle of songs culled from interviews he made with relatives and friends who experienced the horrors of war firsthand. Nevertheless, it packed the most dramatic punch of any of the works on the bill: it was both thoroughly relevant and profoundly disturbing. This is opera as political activism, the sort that Beethoven embraced in Fidelio but has been rarely seen in rep houses since. As Little says in the program:

"Opera is an art form in which the political and the artistic can be fused in a way that expresses the desires - the need - for social change through empathy, not preaching. Empathy fuels the expression of the social, the political, and makes it real. This is the essence of what I call 'socially engaged music.'"

Speaking of the music, the orchestra (led by City Opera music director George Manahan) was driving and propulsive, full of heavy percussion and shrill, piercing strings. James Bobick delivered an astonishing solo performance, his voice ranging from bass to countertenor while running the gamut of emotions familiar to many soldiers: angry, stoic, scared.

In the final section, Little tells the story of a father who receives a home visit from two Marines, to tell him his son has been killed in combat. The music grows heroic as the father torches the Marines' van in protest, then plaintive as he pleads, "Bring back my son!" to anyone who might listen. There was hardly a dry eye in the house as the final notes faded away.

(Unfortunately, I missed Robert Manno's promising Dylan & Caitlin, about the Welsh poet Dylan Thomas and his wife, with a libretto by Welsh playwright Gwynne Edwards. I learned from my next-seat neighbor that Manno is a former Met chorus member, so I'm sure he knows a thing or two about how to write an opera.)

VOX will return for its 10th anniversary next season, despite the arrival of Gerard Mortier as general manager and his many planned changes for City Opera. One would hope he knows enough to leave well enough alone.