HARRISON — The program that the chamber players of the Sebago-Long Lake Music Festival presented focused largely on Franz Schubert, and particularly on the music he wrote just before his death at 31 in 1828.

The program’s main draw – and, on its own, ample justification for its title, “Schubert’s Extraordinary Year – 1828” – was the exquisite “Two Cellos” Quintet in C major (D. 956). But another Schubert gem, the Nottorno in E-flat major (D. 897), probably composed the same year, was included for good measure, as was a contemporary tribute to the composer, John Harbison’s “November 19, 1828,” an otherworldly piano quartet, named for the date of Schubert’s death.

The program opened, though, in a universe quite different from Schubert’s, with the Trio Sonata in C minor from J.S. Bach’s “The Musical Offering,” a work composed shortly after Bach visited the court of Frederick the Great in Potsdam in 1747.

There were some pleasingly subtle touches here. Though you might have been tempted to object that the keyboard line, played by Mihae Lee, the festival’s director, ought to have been heard on the harpsichord instead of the festival’s Petrov piano, the work’s history suggests otherwise: Frederick’s instrument collection included a fortepiano – a delicate-voiced predecessor of the modern piano – which Bach is known to have played for the king.

True, a fortepiano is not quite the same as a modern concert grand, but Lee played it with a light, relaxed touch that approximated the sound of the transitional keyboard instrument, and the modern piano’s firm bass stood in for the cello that would typically have been included in a trio sonata performance. More to the point, Lee’s gently turned keyboard work supported lovely, unpressured readings of the work’s top lines by flutist Susan Rotholz and violinist Philip Palermo, with Rotholz providing thoughtful ornamentation.

If you are wondering where Bach fits into a Schubert program, the Harbison work offered an answer. During the final weeks of his life, Schubert visited Simon Sechter, an older colleague, for lessons in fugue composition. Sechter assigned him a fugue subject based on the letters of Schubert’s name, but Schubert died before he could complete it, so Harbison closed his Schubert tribute by taking up the challenge, actually providing two extremely Bachian fugues instead of one.

Harbison’s work, composed in 1988 and performed here by Lee, violinist Min-Young Kim, violist Laurie Kennedy and cellist Bonnie Thron, is otherwise a fantasy in which Schubert-like thematic fragments – as well as a theme from an unfinished Schubert rondo – are presented through a modern prism. Its movements sound vaguely Schubertian one moment, and both harmonically and structurally alien to Schubert the next. Apart from providing a retrospective rationale for the Bach, it provides an unusual and consistently interesting perspective on Schubert, and how a composer with his melodic gift might write today.

Between the Bach and Harbison works, Palermo, Lee and cellist Eliot Bailen gave a warm, shapely reading of the Notturno, a short work that may have been a rejected movement from one of Schubert’s two complete trios, or perhaps the start of a third.

Schubert’s “Two Cellos” Quintet, a work brimming with bittersweet themes, is one of the glories of the chamber music repertory, and though the DaPonte Quartet played it in Portland in May, this is a piece you can never hear too often. The reading here – by Kim, Palermo, Kennedy, Thron and Bailen – was not always optimally balanced but in the most crucial moments – the warmly harmonized tandem cello (and later violin) theme in the opening movement, and its echo in the finale, as well as the energetic, hearty Scherzo – everything was fully in place, and played with sufficient focus and beauty of tone to drive home the tragedy of Schubert’s early death.

The program was dedicated to Will Hertz, 93, who retired this season as the author of elegant program notes for many organizations, including this festival.

Allan Kozinn is a former music critic and culture writer for The New York Times who lives in Portland. He can be contacted at:

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