When audiences crowd into Avery Fisher Hall this Thursday for the opening of Lincoln Center’s Mostly Mozart Festival, they won’t be looking at what Josh Dachs calls “a picture frame at the end of a long room.” For the 39th annual festival, Mr. Dachs’s theater-design firm, Fisher Dachs Associates, has reconfigured the New York Philharmonic’s home in the manner of an 18th-century concert hall – the first such project in Mostly Mozart’s history.

“The idea started brewing in my mind about two years ago in a serious way,” said the vice president for programming at Lincoln Center, Jane Moss. “It was about wanting to create a festival ambience at Avery Fisher through this new physical envelope.” To create a setting more appropriate for the festival’s smaller chamber orchestra, Fisher Dachs planned a temporary wooden stage extension that reaches 30 feet into the audience, allowing for 233 new seats where Avery Fisher’s usual stage sits.

“Normally, the orchestra plays in what effectively is a nearly sealed box at the end of the hall,” Mr. Dachs said. “It’s like the musicians are in one room and the audience is in another.” In Mr. Dachs’s design, the audience wraps around the stage. The idea is to bring listeners closer to the musicians.

Festival music director Louis Langree, for one, said he looks forward to hearing the first notes played on the new stage. When he became the fulltime director of the festival in 2003, he said, “Everyone wanted to know how I liked Avery Fisher, and I know they wanted me to say I didn’t like it.”

“I really did like it,” he said, and laughed, “but for Mozart repertoire, it’s quite large.” Though Mr. Langree never felt restricted by the original hall, he said the more intimate setting should allow the orchestra to concentrate less on projection and more on the colors and nuance of the music.

The reconfigured stage will be especially suited, Mr. Langree said, to the Tchaikovsky Violin Concerto, which Joshua Bell will play August 16 and 17. He fondly remembers advice from a Russian musicologist who told him that, while conducting the concerto, he should remember Tchaikovsky’s words, “Mozart was my God.” “The orchestration is basically the same as a Mozart symphony,” Mr. Langree pointed out.

In addition to the stage, a new acoustic canopy has been added, which Mr. Dachs said serves a triple purpose. It reflects sound so the musicians can hear one another. It ensures that sound will be evenly distributed. And it provides a platform from which to light the orchestra. Chandelier like pendant lights hang off the canopy, “making the orchestra the absolute focus of the hall,” said Mr. Dachs.

Though the first true dress rehearsal onstage will occur only one day before opening night, Mr. Langree is confident that the musicians and audience alike will love the new design. “Looking at it, I feel like a kid in a toy store. It’s beautiful, magical.” And he’s sure the hall will, above all, appeal to New Yorkers. “It’s very important that an institution like Mostly Mozart remain a place of experimentation,” Mr. Langree said. “What I love about New York audiences is they are not only open to something like this, but excited. And I think they will especially love this.”