Mauceri Resurrects Forgotten Sounds of Germany : Music: The Hollywood Bowl Orchestra conductor is restoring long-neglected 20th-Century works stifled by the Third Reich.

“Lost treasures” is a phrase that often comes up in conversations with John Mauceri these days.

The American conductor, founder and music director of the Hollywood Bowl Orchestra since its first season, two years ago, is on a search.

He is looking for the best of a large body of classical works that have been long-lost--or at the least, long-neglected.

These are the scores suppressed by Germany’s Third Reich in the 1930s and ‘40s. They were dubbed “Entartete Musik” (degenerate music) and banned because their composers were Jewish, or avant-gardists, or because they delved into subjects considered degenerate--such as jazz or happy race relations.

This treasure-trove is “practically a whole new category of music,” says Marlisa Monroe of Philips Classics, because it is a body of 20th-Century music that has been either neglected or unknown. In this category are such contrasting and geographically distant figures as Hindemith, Franz Waxman, Walter Braunfels and Ernst Toch.

This spring, a few weeks before the release of Mauceri’s latest Hollywood Bowl Orchestra album (on Philips), the first two installments in the Entartete Musik series (on London) reached the record stores. It is an incontrovertibly ambitious project that the conductor says could take as long as 15 years to complete. At this point, release dates reach into 1996.

The starters are two never-before-recorded operas, Erich Wolfgang Korngold’s erotic “Das Wunder der Heliane” and Ernst Krenek’s jazzy “Jonny Spielt Auf.”

These two works, Mauceri says, both given first performances in 1927, have long been uncirculated in the operatic world. (After many years, “Jonny” was exhumed by Long Beach Opera in 1986.) To restore them, and any number of other forgotten compositions, to the recognition they deserve is the aim of this project.

“Think about it,” the 47-year-old Mauceri said recently, “if we knew Beethoven as only a name in the music-history books, but had never heard much of his music, and someone found one of his symphonies in a publisher’s back room, then made it available, what would we say?

“What could we think, if all our knowledge of this writer was the limited evidence of, say, the Second Symphony? Could we make an assessment based on a tiny fraction of his output? Could we decide to let his reputation live or die on so little aural data?

“That’s the position I find myself in, visiting publishers’ headquarters and reading scores from six decades ago, researching music no one has seen, much less heard, in half a century. It’s a tremendous responsibility, having to say yes or no to the survival--outside the archives--of certain unknown works.”

Not all of the composers are as well-known, if still-neglected, as the hyper-romantic Korngold and the cerebral Krenek, two 20th-Century writers who made notable careers in the United States after they left Europe in the 1930s.

There was Viktor Ullmann, who died in the Auschwitz concentration camp in 1944, but continued to write up to the end; Berthold Goldschmidt, who went to England in 1935 and lives there still, his compositional career permanently existing outside the mainstream; and Franz Schreker, Goldschmidt’s teacher at the Berlin State Academy, who died of a heart attack in 1934 after the Nazi regime discredited him and banned his music.

“An entire generation of German composers--Jewish and non-Jewish--and their works was lost to the world because of the war and because of the artistic policies of the Third Reich,” Mauceri says.

“In a sense, we are now picking up the pieces.”