Daniel Barenboim, Michael Barenboim, Kian Soltani & Ben Goldscheider

became a success story—but in his persona as an exceptional pianist rather than as a composer. Mozart had forged the way for this pattern of surviving as a freelance musician over the previous decade, yet he was already known as a composer by the time he made his move to Vienna; Mozart’s celebrity as a keyboard virtuoso was, in a sense, a sideline that he could use to support himself financially while the market and public taste still allowed for it.

Beethoven, too, had been industriously building up a portfolio of compositions since his teenage years in Bonn.

His first work to appear, in fact, was the “Dressler” Variations for keyboard (WoO 63), which was published as early as 1782. Yet Beethoven waited to make a public declaration in print of his serious ambitions as a composer until 1795, when he assembled the set of three piano trios that were issued in Vienna as Opus 1.

The format of the piano trio in itself was a telling choice.

Music publishers were responding to an increased demand among amateur musicians for new pieces to play in domestic settings. Among the potential chamber music formats, the piano trio was especially appealing for this growing market of amateurs. The trio featured the piano, Beethoven’s instrument, in a prominent role. Perhaps most importantly, it afforded more “space” to carve out his identity vis-à-vis his predecessors Mozart and Haydn than, say, the string quartet, which both had cultivated to a much greater extent—a format in which Beethoven waited until 1801 to make his first publication, though he would advance the quartet into spheres completely unprecedented. For the time being, the piano trio offered a perfect niche to announce his identity as a composer.

Yet along with their marketable aspect, in the Op. 1 Trios Beethoven already poses intense challenges, making clear an unusual degree of ambitiousness that we know astonished and impressed his contemporaries. The precedents set by Haydn and Mozart in their respective piano trios were typically cast in three movements, while all three of the Op. 1 Trios are conceived on the grand scale, in four movements (a scale also found in the first piano sonatas, similarly from this period). “From the first,” writes the biographer Maynard Solomon, “Beethoven was thinking in terms of formal expansion, long-range harmonic action, and heightened rhetoric.”

The Trio in G major, published as the second of the set, 14