It is 40 years since Leon Fleisher's appointment as Andrew W. Mellon Professor of Piano at the Peabody Conservatory of Music. The conservatory celebrates the anniversary this week with a three-day festival in Fleisher's honor.

The festival concludes Wednesday evening with a black-tie, by- invitation-only dinner in the George Peabody Library. Actress Claire Bloom will act as mistress of ceremonies to titled nobility and musical luminaries who have come from all over the globe to honor Fleisher. The pianist will receive from King Albert II one of Belgium's highest honors: Commander in the Order of Leopold II.

But the greater part of the festivities will be devoted to three marathon evenings in which Fleisher's students will perform nearly all of Brahms' solo piano music.

That Fleisher is being honored in so grand a manner is not a surprise. A Peabody news release characterizes Fleisher as "one of the most famous members of the Peabody faculty." That's a little like calling Babe Ruth one of the most famous players on the 1927 Yankees. Peabody's faculty does include distinguished teachers and musicians. But Fleisher's the Franchise. It's no exaggeration to call him the most famous living musician who also happens to be a full-time teacher.

Why Brahms? Partly because Peabody celebrated another Fleisher anniversary only a few years ago with a Beethoven marathon. Of the great composers with whom Fleisher is closely associated that leaves Mozart, Schubert and Brahms. Mozart was not a possibility because that composer's piano music -- as Fleisher's teacher, Artur Schnabel, once famously remarked -- is "too easy for children and too difficult for professionals." (The truth is that most of Mozart's solo piano music -- not his works for piano and orchestra -- is not terribly interesting and would make for a tedious festival.)

Schubert must have been eliminated because so many of his 22 sonatas and other keyboard works are either incomplete or incompletely preserved. Moreover, some of them remain so obscure that time spent learning them would be -- for a student, at least -- time wasted.

That leaves us with Brahms.

Like almost every other great composer, Brahms was also a great pianist. He didn't like to practice and he scorned empty virtuosity, but he's still the composer who was enough of a monster pianist to have conceived, composed and performed his own "Paganini Variations" -- one of the greatest and most baffling challenges to virtuosos.

The piano constitutes the central element in Brahms' compositional life, and it was during his lifetime that the piano evolved into the instrument we know today. When Brahms was a boy in the late 1830s, he learned to play on light instruments not very different from those Beethoven and Schubert used. By the time he completed the "Paganini Variations" in 1863, Brahms was writing for a distinctly modern-sounding instrument -- brighter, more metallic and richer in tone. His last works were written for an instrument virtually identical to today's concert grands.

The piano music shows us, neatly and chronologically, the three major facets of Brahms' musical personality: His admiration for Beethoven and his desire to write in the grand manner (the sonatas); his growing self-criticism and his love of early music (the variations, with their strict counterpoint and use of fugues); the condensed lyricism of his sadness and nostalgia at the end of his life (the late music).

Here's a guide to some of the most important pieces that will be performed this week.

* The sonatas. Twenty-five years after the deaths of Beethoven and Schubert, it had become clear the Romantics no longer used sonatas as their chief outlets for piano writing. But when the 20-year-old Brahms visited the Schumanns for the first time in 1853, he arrived "fully armed" (in Schumann's words) with two sonatas (in F-sharp minor and C major) finished and a third (in F minor) in his head.

The F-sharp minor, numbered second but actually written first, is lavishly virtuosic and daringly rhapsodic. From the opening onslaught of double octaves to the cadenza-like finale, it approaches Liszt more closely than any of Brahms' subsequent works. The opening of the C Major Sonata proclaims the youngster's worship of Beethoven: the rhythm resembles that of the latter's "Hammerklavier" Sonata and its downward keyboard plunge that of the "Waldstein."

The 40-minute Sonata No. 3 in F Minor is Brahms' first genuine masterpiece. Of the slow movement, pianist Claudio Arrau said: "For me, it is the most beautiful love music after 'Tristan.' And the most erotic -- if you really let go, without any embarrassment. And if you play it slowly enough."

Brahms lived another 44 years, but he never wrote another piano sonata.

* The variations. After Bach and Beethoven, Brahms is the greatest master of variation form. His two greatest works in the genre are the "Handel Variations" (Opus 24) of 1861 and, two years later, the "Paganini Variations" (Opus 35).

Wagner said about the "Handel Variations" that it showed "what could still be done with the old forms," a grudging but genuine acknowledgment of the work's power and inventiveness. It was Brahms' personal favorite, and it demonstrates how the youthful exuberance of the early sonatas has been channeled into organic necessity by the composer's careful study of Bach's "The Well-Tempered Clavier."

Its 25 variations visit not only Bach and Handel, but also Couperin and Beethoven, and conclude with a triumphant fugue.

* The late works. In 1892 and 1893, as he was turning 60 and had less than five years to live, Brahms published four collections of shorter pieces: Opus 116, 117, 118 and 119. These collections, containing 20 pieces, rank among his finest achievements.

"It is with the late piano works that we reach Brahms' most personal music for his chosen instrument," Artur Rubinstein wrote. "Brahms in his final years produced serene and nostalgic music that was ever more inward in mood. ... They are so intensely intimate that one cannot really convey their substance to a large audience."

Sharp insights from a great Brahms interpreter. But while these pieces are deeply nostalgic, serene is not an adjective I would use to describe them. Many of the fantasies in the Opus 116 set are restless, agitated, even angry. And Brahms himself referred to the three intermezzi of Opus 117 as "cradlesongs of my sorrows."

Unlike the early sonatas and the middle-period sets of variations, the composer does not use the musical forms of the past. But these works -- like other late pieces by other great composers -- bid farewell to a musical world that no longer exists.

Perhaps the most poignant of these pieces is the tragic E-Flat Minor Intermezzo that closes Opus 118. The modifiers for the Andante tempo marking are "largo e mesto" ("slow and mournful"). Despair and grief mark the forlorn theme that is developed to a shattering climax and then comes to a subdued, keening close that only intensifies the uncertainty.

At the end of his life and at the end of the last century, Brahms seems to have reached the conclusion that the traditional musical language he loved can remain viable only if it reflects upon its own disintegration. Brahms' prophecy, troubling then, is even more disturbing today.

Brahms, Brahms, Brahms

What: Leon Fleisher's students play piano works by Brahms in Friedberg Hall.

When: Monday 7 p.m.-11 p.m., Tuesday 7 p.m.-11 p.m. and Wednesday 7 p.m.-8 p.m.

Tickets: All three nights are free and open to the public, but tickets are required Wednesday.

Call: 410-659-8124

Pub Date: 04/25/99