PHILADELPHIA -- Musicians from Austria and Philadelphia will stand shoulder to shoulder today to perform a musical plea for peace and understanding as part of the Constitutional Bicentennial observance and the Independence Week celebration.

The event at the Academy of Music will be the American premiere of "Missa Pacis," a work by Viennese composer Roland Baumgartner with cross-cultural texts by Jochen Bauer. Free performances will be held today and tomorrow.

The 31-year-old composer will conduct an orchestra that mingles Philadelphia players with members of the Vienna Symphony and the Austrian Radio Orchestra; a vocal ensemble that mixes the Pennsylvania Pro Musica chorus and the Mozart contingent of the Vienna Boys Choir, and soloists that include European and American concert singers, an English rock singer and a Senegalese percussion duo called the Kings of Africa.

Mounting the event has been a year-long preoccupation of the composer, the librettist, the city of Vienna, Pennsylvania Pro Musica Director Franklin Zimmerman, the Philadelphia city representative and a little-known organization called Anima International, based in Philadelphia.

The idea originated with Barbara McEly, an actress who established Anima International as a means of promoting international understanding through the arts. She was looking around Europe for theatrical events that might have some meaning to American audiences, she said, when she met Baumgartner and stage director Bauer.

Her husband Paul Kleindorfer explained that when Vienna's mayor became involved with the project, "he insisted that the performances be free. He told us this was to be a gift from the city of Vienna. He told me, 'This is the 40th anniversary of the Marshall Plan. When you {Americans} brought that help to us, you didn't ask the price. We are still grateful.' "