Period-instrument Beethoven isn't exactly revolutionary in 2006. Boston Baroque, Tafelmusik in Toronto and Philharmonia Baroque in San Francisco all perform the symphonies; for European groups like the Orchestra of the Age of Enlightenment (London), the Orchestra of the 18th Century (Amsterdam) and the Orchestre des Champs-Elyses (Paris), Beethoven is a regular part of the musical diet.

But in New York, ever since the collapse of the Classical Band in the early 1990s, what period-instrument Beethoven we get (except, perhaps for some chamber music) is imported from Europe.

The Clarion Music Society will start to address that lack tomorrow night with the first concert of its 2006-07 season. At 8 pm at the Church of St. Ignatius Loyola (Park Avenue and East 84th St. in Manhattan), Clarion artistic director Steven Fox will conduct the society's chorus and period-instrument orchestra in an all-Beethoven program featuring the Symphony No. 2, the cantata Meeresstille und glьckliche Fahrt ("Calm Sea and Prosperous Voyage") and the Mass in C major.

Founded in 1957 by philanthropist Thomas Newbold Morgan and conductor/musicologist Newell Jenkins, the Clarion Music Society offered regular concerts in New York for four decades, giving many 18th-century works their first modern performances in the city. Following the death of Jenkins in 1996, Clarion suspended its performing activities for several years and functioned as a grant-making foundation.

That changed with the arrival of Steven Fox as Clarion's artistic director in late 2005. Now 28, the conductor/scholar/singer — who founded Russia's first period-instrument orchestra, Musica Antiqua St. Petersburg — led the society's musicians in an all-Mozart program last January that drew not only audience acclaim but financial support from both individuals and foundations.

That support has enabled Clarion to resume its mission of presenting in concert lesser-known works on period instruments, and the society will be giving three concerts this season. In addition to tomorrow night's Beethoven program, Fox will conduct a concert of works by Haydn and C. P. E. Bach at the Morgan Library's new Gilder Lerhman Hall on February 20, and a program called "The Eastern Enlightenment," featuring Russian and Polish music from the late 18th and early 19th centuries, on May 8.

More information about the Clarion Music Society and its concert season can be found at www.clarionmusic.org.