For the last two years Grand Harmonie (the term Harmonie broadly means wind ensemble) has presented concerts of early chamber music—and sometimes larger ensemble music—that feature historically accurate wind and brass instruments. Now the group of young musicians from New York and Boston is growing into a full period instrument orchestra focused on 19th-century repertoire. ”We might still play Mozart or Haydn, but a lot of 19th-century repertoire has yet to be explored,” says Grand Harmonie organizer and natural hornist Yoni Kahn. Some of this repertoire is rarely played on period instruments, and some of it is rarely performed at all.

So on February 28^th the ensemble will perform Beethoven’s 8th Symphony in celebration of the 200^th anniversary of its premiere, and also offer the 21^st-century professional premiere of a recently discovered horn concerto by Jean Baptiste Édouard Du Puy, a Swiss musician born the same year as Beethoven, who worked as a composer, opera singer, and violinist in Scandinavia and France. His horn concerto was discovered in the Royal Library of Stockholm in 2012 by Bertil Van Boer, a musicologist from Western Washington University, who passed it on to Michael Ruhling, the president of the Haydn Society of North America.

Ruhling performed the work with the Rochester Institute of Technology Orchestra and horn soloists James Hampson. The two will now give the professional period instrument premiere of the concerto with Grand Harmonie. ”Du Puy adored Mozart and his music sounds Mozartian, but also French,” Hampson says. He believes the concerto was written during Du Puy’s stay in Paris for Louis-Françcois Dauprat, the leading horn virtuoso of the time. “There’s more notes in it than a violin concerto,” Hampson explains. Dauprat was likely the only person in Europe with the right skills to play the piece.

Throughout the 19^th century, brass instrument technology and performance practice changed rapidly. New models of valve instruments were invented every few years and players struggled to master the new technologies. Hampson points out that valve horn parts that survive from the early 19^th century often have fingerings penciled in above nearly every note. Older natural horns continued to be played alongside new instruments, and solo compositions were always written with a specific player in mind, taking into account his unique technical strengths and specific equipment.

So when performers today use a standardized modern horn for the entire span of 19th century orchestral music, they lose access to an entire spectrum of possible colors. This is something the historical performance movement can restore to late classical and early Romantic repertoire, both through performance techniques that attempt to match historical descriptions of tone color, and through the use of period instruments. For the Du Puy concerto, Hampson will use an antique natural horn made around 1810 in Paris—the same time and place the piece was written.

Resurrecting newly re-discovered repertoire can also resurrect mostly forgotten biographical anecdotes. It turns out that Du Puy lived a life as colorful as the tone of the natural horn for which he wrote. He gave the Scandinavian premiere of Mozart’s Don Giovanni and then, according to Hampson, “literally became Don Giovanni.” Among other transgressions, the composer had an affair with a Danish princess that ended in exile for them both. But Du Puy later found his way to Stockholm where he worked for the rest of his life.

Some of  Grand Harmonie’s musicians also lead interesting lives, of a different sort. Hampson will be the first person in the United States to complete a doctorate in natural horn when he graduates from Boston University. Kahn, on the other hand, is working on a Ph.D. in physics at MIT when he isn’t performing.

On Friday night,  Grand Harmonie will also perform Beethoven’s 8th Symphony. “It’s definitely one of the lesser-performed symphonies,” Kahn says. “But there are some crazy explosive Beethoven moments that come out in the last movement, and there’s always energy under the surface.” The program will begin with an obscure symphony-in-miniature by Michael Haydn.

“We’re sort of rediscovering an art,” Hampson concludes. “But I think early music is the music of now.”

Grand Harmonie will present “Beethoven: A Premiere Anniversary” on Friday, February 28^th, at 7:30 PM at the First Church, Congregational in Harvard Square.