All-Mozart concerts are no longer the rage they were in the 1980s and '90s, but Mozart fits so well into the Hawai'i Theatre that the program seems a natural choice for this season.

The Hawai'i Theatre is about the same size as 18th-century theaters, and its stage comfortably accommodates an orchestra of 35 to 40 musicians, about the size of the grand orchestras in Mozart's day. Small by modern standards, an orchestra of 35 to 40 fills the space in Hawai'i Theatre physically as well as aurally and gives the impression of being large while retaining the clarity and intimacy of being small.

In other words, perfect for Mozart.

The centerpiece for Saturday's program was Mozart's Sinfonia Concertante featuring four principals from the Honolulu Symphony: Scott Janusch (oboe), Scott Anderson (clarinet), Paul Barrett (bassoon), and Wade Butin (French horn).

A sinfonia concertante is less a symphony than a concerto for more than one soloist: three movements (as opposed to a symphony's usual four), alternating sections for full orchestra with ones for soloists. Solo sections feature one instrument, different combinations of solo-ists, or all four, either alone or accompanied by the orchestra. Part of the pleasure is hearing the shifting timbres and the interplay between different instrumental voices.

Saturday's performance, under the direction of guest conductor Heiichiro Ohyama, was utterly charming, and Janusch, Anderson, Barrett and Butin were terrific, individually and severally. Vibrant, exciting, expressive, they revealed themselves as among the Honolulu Symphony's core strengths.

From my seat, balance was quite good — all four clearly audible, with the oboe most prominent and the bassoon least prominent throughout — but sound varies markedly in this theater. Some in the audience apparently found it more difficult to hear one or another of the soloists.

The way sound bounces around the Hawai'i Theatre may also explain the balance of the full orchestra: throughout, higher, brighter sounds (violins, upper woodwinds, brass, timpani) overshadowed lower, darker sounds (cellos, string basses, bassoons), yielding a less-warm sound. Fortunately, for this concert, Maestro Ohyama moved the orchestra closer to the front of the stage and added shells (large panels to direct sound) around the orchestra, so that the back half of the ensemble could be heard beyond the curtains.

Although the theater's dry sound is not particularly flattering for orchestras, exposing as it does every uncertainty of intonation and every imprecision of entrance, it does allow audiences to revel in Mozart's inner lines and transparent textures.

Ohyama made the most of those inner lines on Saturday, attending to each phrase and creating beautifully crafted moments in the two symphonies presented, the "little" G minor, K.183, and the first of Mozart's final three "great" symphonies, K.543 in E-flat major.

Ohyama proved to be a master of detail, and the openings of each movement were outstanding. Although his larger structures tended to devolve into moments, Ohyama was especially deft at creating distinct moods and portraying the dramatic characters that Mozart wove into his symphonies.

The essential aspect of Ohyama's conducting seemed to be control: whether in delicate pianissimos or in grand climaxes, his conducting conveyed a wealth of emotion within bounds of propriety.

On Saturday, his was a well-bridled passion.