IT’S BEETHOVEN, NOT MARCHES, FOR HANOVER BAND

When is an orchestra a band?

When band is used in the 18th-Century sense of “instrumental ensemble,” when the ensemble is modeled on the Viennese Akademie orchestras of the early 19th Century and when its name derives from the family of German kings of the House of Hanover.

As in Hanover Band, the conductorless, 35-member, authentic-instrument orchestra from Great Britain, which makes its first Southern California appearances tonight and Sunday at Ambassador Auditorium and Royce Hall, respectively.

Caroline Brown, cellist, founder and artistic director of the band, outlined the chamber orchestra’s musical profile in a phone call from Virginia, where the group made its U.S. debut, last week.

“For the time being, we are specializing in Beethoven,” said Brown, who added that she is not really the musical leader of the ensemble. That job belongs to first violinist Monica Huggett, who, when she is not touring with the Hanover Band, holds a similar post in Holland, with the Amsterdam Baroque Orchestra.

Huggett, according to Brown, “leads with her bow, chooses the tempos and has the responsibility of bringing off the performances.”

This weekend, the ensemble offers two different Beethoven programs. The lengthy agenda for tonight at Ambassador is an actual re-creation of a concert Beethoven himself produced at the Burgtheater in Vienna on April 2, 1800.

That program, intended for the composer’s benefit (a common practice at that time), provided at its conclusion the premiere performance of Beethoven’s First Symphony. But, before that, it warmed up with Mozart’s Symphony No. 40 and vocal music by Haydn, and offered two other recent Beethoven works, the First Piano Concerto and the Septet, Opus 20.

At UCLA, Sunday night at 8, the program lists the “Prometheus” Overture, the Violin Concerto (with Huggett as soloist) and the Symphony No. 2.

Though the Hanover Band was originally scheduled to tour with a restored Broadwood fortepiano of the period, Brown says, the keyboard soloist (Mary Verney) “broke her thumb, and we have brought Melvyn Tan to play the concerto on a fortepiano we are getting in California.”

To produce an authentic early-19th-Century orchestral sound, Brown says, the band employs string instruments with thinner catgut (rather than modern metal) strings, wind instruments of all-wood construction and valveless brass instruments. In addition, string players make more sparing use of vibrato, and the entire ensemble tunes to Classical period pitch of A equals 430.

“We have tried various pitches, most recently 438. We, or rather the instruments, didn’t seem to be happy at all at 438.”

Guest soloists with the Hanover Band at Ambassador Auditorium tonight will be American singers Delcina Stevenson and Jan Opalach, who will sing excerpts from Haydn’s “Creation.”