Rather than present a keynote speaker on Wednesday, the National Performing Arts Convention's opening event will unleash a panorama of Pittsburgh artists that will define a distinctly American arts landscape. Moving from stage to street and back again, the festivities will encompass Bessie Smith and Blue Ladies, marching bands and the Mendelssohn Choir, Shostakovich and Sousa.

This sprawling artistic portrait will be divided into three segments, starting with John Conklin's massive opening collage, "Variations on America -- A Work in Progress," at the David L. Lawrence Convention Center at 4 p.m., followed by a "Street Scene" along Penn Avenue with interactive dance and music and capped with the Mendelssohn Choir and Pittsburgh Ballet Theatre in Bach's "Magnificat" at Heinz Hall at 8:30 p.m.

It was Opera America's Mark Scorca who suggested the collage. He had observed Conklin's Glimmerglass Opera productions in Cooperstown, N.Y., each of which included a scrapbook of paintings, essays, sayings and biographies about an opera. Intrigued by the concept, he suggested an expanded version of about an hour, something that approximates the length of a keynote speech, with Conklin as director.

Conklin, who also teaches for New York University's Tisch School for the Arts and has designed for opera and theater around the world, tapped a quote from Ralph Ellison, who, having observed artist Romare Bearden's work, described America as "a collage of a nation." Using that as inspiration, Conklin assembled a living quilt of Pittsburgh performers, one that will include nine individual actors, Carnegie Mellon University's Starling String Quartet, a gospel choir comprising local church choir members, professionals and students from Pittsburgh High School for the Creative and Performing Arts, baritone James Maddalena and mezzo-soprano Kristine Jepson from Pittsburgh Opera's cast of "Dead Man Walking," gifted young cellist Clare Bradford and Mikhail Istomin of the Pittsburgh Symphony Orchestra, the South Fayette and West Allegheny High School marching bands, the Wheeling Symphony Orchestra and the Boilermaker Jazz Band.

Like a keynote speech, Conklin says, "It will raise questions, it will stimulate discussion, it will act as a bit of an inspiration, as a kind of call to action" for an anticipated audience of 5,000. More than that, Conklin says, it will be "made up of the very elements of people who are there at the convention," enhanced by four large video screens.

With only three days for rehearsal, the collage will take the form of a work in progress.

"It's about what we should be doing, not just about what we've done," says Conklin. "It's just the way we are. We're constantly trying new things, we're bringing up questions, we're trying different solutions."

That theme will be carried on as conventioneers sweep out onto Penn Avenue, to be greeted there by the thundering rhythms of Umoja African Arts Drum and Dance Ensemble and a three-block-long party labeled "Street Scene."

Pittsburgh Opera's Mark Weinstein hired Three Rivers Arts Festival's Elizabeth Reiss to coordinate the event. Determined to provide a visual impact, she had festival curator Katherine Talcott identify storefronts along Penn Avenue and select 12 local artists to design installations. Pittsburgh native Kristoffer Smith also created a 64-foot-long mural, divided into eight movable sections and full of colorful images, as another backdrop for the performance pods scattered along the corridor.

Reiss then engaged multidisciplinary arts organization FLUX to bring in 10 musical acts that will be interspersed among the dance scenes produced by Attack Theatre's Michele de la Reza and Peter Kope.

De la Reza calls it "a collision of the spontaneous and the planned. When you walk through determines what you will see."

Strollers might have to avoid a bar brawl at Mark's Bar and Grill that spills out into the street, but they can learn some evasive hip-hop moves from Spidey & Poppy Kid or Crutchmaster Bill Shannon.

Pittsburgh Dance Connection's Gina Desko and her Blue Ladies will share the action with Melanie Miller's spy network from Junction Dance Theatre and an improvisatory "trio" with Dance Alloy's Mike Walsh and LABCO Dance's Gwen Ritchie. Onlookers can interact in other ways while they learn Pittsburgh's "ceremonial rituals," such as the Chicken Dance.

And "Oh, What a Feeling" strollers will get from a six-minute dance retrospective of the movie "Flashdance," using a nongender-biased cast from Point Park University, Slippery Rock University, University of Pittsburgh, Wooster, Ohio, and surprise guests.

The strollers will congregate around the Cajun spice of Mon Gumbo, where Susan Waggoner and Rosemary Nulton of Venez au Bal will teach onlookers Zydeco moves.

After a reception at the Benedum Center, conference members can choose to move on to Heinz Hall, where there will be yet another Pittsburgh collaboration from the Mendelssohn Choir and Pittsburgh Ballet Theatre.

With two popular successes with cult favorite "Carmina Burana" under their belt, both the Mendelssohn's Robert Page and PBT's Terrence Orr were open for more opportunities.

It was Page who suggested that they do something for the National Performing Arts Convention. Orr had seen Salvatore Aiello's "Magnificat" at North Carolina Dance Theatre in 1999, just after Aiello passed away. "I liked Sal's style, with its classical ballet technique in a contemporary mode," he says. "It's a group effort that emulates the joyful quality in the score. With 17 dancers in beige costumes and 60 choristers and four soloists on stage with them, it has a powerful look."

Jerry Kumery, an assistant to Aiello who staged the ballet for PBT, calls it "a direct communion between God and man. It is inspired by the music and the text, with a body-friendly, organic flow that is unbelievably musical."

"I've just been waiting for a chance to celebrate, to put 'Magnificat' on a program," Orr says. "Few know about Sal's work -- he was ahead of his time."