Revision and refinement were keys to Brahms Sonata

On Sunday, pianists Marc-André Hamelin and Emanuel Ax perform a duo piano recital at Symphony Hall including the Op. 34b Sonata for Two Pianos by Johannes Brahms. The piece was a collateral product of the composer’s perfectionism: It started out as a string quintet, then was translated into the Sonata, and finally reached its most familiar form as the Op. 34 Piano Quintet.

Brahms (inset) was his own fiercest critic, but his friends could give him competition. After initial enthusiasm for the string quintet, violinist Joseph Joachim decided that it was lacking “in a word, charm.” Brahms then fashioned the two-piano version and gave a well-received performance in Vienna with the Polish virtuoso Carl Tausig. Still, his friends were doubtful. Clara Schumann — having played through the score with conductor Hermann Levi — was optimistically pessimistic. “Even the most beautiful ideas go for nothing on the piano,” she wrote, “please — remodel it once more!”

The Piano Quintet was, finally, judged a success. “You have turned a monotonous work for two pianos into a thing of great beauty,” Levi applauded. To Brahms — who put painstaking effort into structure and counterpoint — this must have been like being told that a favorite child seemed much less ugly in a new dress. Perhaps that is why he went ahead and published the Sonata anyway, shrugging to his publisher, “It appeals to me in this form.”

In the Quintet, the contrast in sound between piano and strings makes some of the musical back-and-forth more obvious. The manuscript for the Sonata, now at the Morgan Library in New York, is full of penciled revisions reassigning material to one or the other pianist, an attempt to realize spatially what the Quintet accomplished through timbre. But in other ways, the Sonata gives a more penetrating account of the music’s inner workings. Focused by the pianos’ clarity, lean and unsentimental, the Sonata sounds modern in a way that the Quintet doesn’t.

Arnold Schoenberg — who knew something about modernism and its assertion — always gave Brahms credit as an innovator, insisting that Brahms had advanced Classical-era ideas of form and balance to the doorstep of 20th-century modernism: “[A]t a time when all believed in ‘expression,’ Brahms, without renouncing beauty and emotion, proved to be a progressive in a field which had not been cultivated for half a century.” Brahms rewired Mozart and Haydn for the Romantic era; the Sonata for Two Pianos is like a peek at the schematic.

Celebrity Series of Boston presents pianists Marc-André Hamelin and Emanuel Ax, April 13 at 3:00 p.m. at Symphony Hall. Tickets: $30-$105. www.celebrityseries.org