The decision to perform classical repertoire on historically accurate instruments can be motivated by purism, curiosity, or artistic choice. In other words, some believe that an ideal performance should be as close as possible to what the composer heard in his day, others feel period performances represent musicologically interesting alternatives, and then there are some who find expressive possibilities in period instruments which are unavailable on modern equipment.

A new, historically-informed ensemble dedicated to 19^th-century music, Grand Harmonie seems unfocused. It’s not clear from the performances or written materials why the group does what it does. At the core there is a period wind band, but on Saturday night, GH’s first season concluded with a full orchestra concert at All Saints Parish in Brookline.

Gioachino Rossini’s overture to La Cenerentola, a quintessential Italian overture ending with one of Rossini’s hallmark orchestral crescendos, was the opener. But unless you’re a purist, it’s not clear this is a piece that offers anything new under the period instrument treatment. Grand Harmonie is presenting La Cenerentola (under its English title, Cinderella) with the Boston Opera Collaborative in August. Perhaps the full opera will offer greater opportunities to hear what these instruments and players can do for this repertoire.

Up next, Carl Maria von Weber’s Clarinet Concerto No. 1 had curiosity value, but little musical interest. Thomas Carroll performed on a 12-key reproduction of an early 19^th-century clarinet. The sound was brighter and a more open than on the modern instrument, but this color seemed ill at ease against the F minor setting of the first movement. Weber remains a solidly second tier composer: he can draw dark colors in harmony and timber, but it never quite rings true in the larger structure. This glibness also extends to the sprightly finale: an odd false ending and lots of filler work against the potential meaning and resonance of the music. Carroll carried the notes he was given with finesse, but perhaps he could have found a better showcase for his instrument and his musicianship.

Felix Mendelssohn’s Symphony No. 3, “Scottish,” filled the second half, and finally offered a chance to hear the real expressive possibilities of the period instruments. Solos in the winds were excellent, with Kristin Olson particularly standing out on the oboe for her tone and phrasing. The period brass section produced a wilder sound, with hunting horn calls taking on a bracing stridency. Sometimes, however, the ensemble intonation wavered in the winds and the details of inner voices lacked precision, particularly in the second movement. But the performance, led by conductor Adam Kerry Boyles, was nonetheless compelling and convincing, and the gut strings laid down a taut and colorful canvas. This is the kind of rep for which historically informed performance can really offer a novel artistic angle.

As a new group, Grand Harmonie is still finding its way. Are they a wind band, an orchestra, or a collective of musicians offering concerts in a variety of configuration? Time will tell. So far the group seems to have grown naturally and is run by its core personnel without an artistic director. However its members decide to structure themselves, hopefully a coherent point of view will emerge in the coming seasons to support and motivate their music making.

Benjamin Pesetsky is a Cambridge-based composer who’s recently been in residence at the Banff Centre and the Hambidge Center. Before that he attended Bard College where he studied with Joan Tower and George Tsontakis and earned a B.M. in composition and a B.A. in philosophy.