As music director of both the Los Angeles Opera and the Deutsche Sinfonie Orchester, conductor Kent Nagano, 53, has earned a reputation for imaginative programming, intellectual curiosity, and a visionary sense of musical connections‹qualities that will be strongly in evidence in his program during the Philharmonic Festival: Visions of the Beyond.

First will be selections from Johann Sebastian Bach's masterpiece, The Art of the Fugue. Bach wrote this set of 20 fugues and canons without indicating any instrumentation: it is most often performed on keyboard instruments. "As a late work of Bach it reflects his tremendous spirituality," says Mr. Nagano, "but in terms of precise orchestration, one cannot know. I felt there should be a way to bring this music to the concert stage."

His way was to commission orchestrations from Ichido Nodaira [pronounced no-DIE-ra], one of Japan's most accomplished composers. Mr. Nagano praises Nodaira's instrumentations as "extraordinarily provocative." For instance, he sets one rapid fugal passage for vibraphone, celesta, and marimba‹a choice that Mr. Nagano insists is "absolutely fidèle to the original fugues; these are not arrangements."

Mr. Nagano has also programmed the composer's Concerto for Violin and Oboe in D-minor, BWV 1060, in its original orchestration, a work which, the conductor says, "offers another chance to appreciate Bach's visionary approach to composition."

Mr. Nagano closes with Olivier Messiaen's Éclairs sur l'au-delà . . . (Illuminations of the Beyond), a profoundly colorful contemplation of life after death, and a New York Philharmonic commission, completed by Messiaen shortly before his death in 1992. Mr. Nagano, who lived as pupil and friend with Messiaen and his wife, the pianist Yvonne Loriod, in 1982 and 1983, recalls that when he received a copy of Éclairs from the composer, he realized "it was at least one of Messiaen's greatest works, if not the greatest one.

"It embraces Messiaen's entire musical language," Mr. Nagano observes, "somehow refined, concentrated, and polished to the point of perfection." As The Art of the Fugue represents the culmination of Bach's work, so Messiaen's Éclairs represents the valediction‹musical and spiritual‹of one of the 20th century's most creative voices.

Barrymore Laurence Scherer is a classical music critic for The Wall Street Journal.