Los Angeles Chamber Orchestra at the Alex Theatre

No fewer than seven of the programs on the Los Angeles Chamber Orchestra schedule this season -- in other words, most of them -- contain West Coast, U.S. or world premieres. This proliferation of new music is due, no doubt, to the season-long celebration of the orchestra’s 40th anniversary as well as the LACO’s laudable commissioning program already in place.

Conservatives may grumble at this, though they still will be getting several helpings of Bach, Beethoven and friends this season. Yet even these audience members might have been among those in the Alex Theatre on Saturday night who were giving the new work of the evening a louder, more enthusiastic ovation than that of Mozart -- currently the world’s most popular classical composer, according to some polls.

The new piece -- a world premiere titled “ceLebrACiOn,” with the orchestra’s initials in pointed uppercase -- came from the ensemble’s longtime principal horn Richard Todd, and it is a beaut. Less than seven minutes long, it finds Todd, one of just a handful of jazzers among French hornists, playing good, soulful tunes over a variety of swinging Afro-Cuban grooves and big-band riffing from the trumpets. You could call this Todd’s Cuban Overture, with a dash of cinema built in. It would make a smashing vehicle for Gustavo Dudamel when he arrives in town.

The other burst of enterprise of the night was the Concerto for Seven Wind Instruments, Percussion and Strings (1949) by Frank Martin, the prolific Swiss composer who, despite being well represented in CD catalogs, doesn’t get much live exposure these days. Somehow, this meticulously constructed modern concerto grosso (think Hindemith, and you’re on the way to pinpointing the style) just misses the mark of greatness, though there is a nifty solo part for timpani. Conductor Jeffrey Kahane, with help from the group’s outstanding wind soloists, gave the piece a good workout -- its first LACO performance since 1983 in the Gerard Schwarz era.

Before his own piece, Todd took on the Mozart Horn Concerto No. 4. It’s no walk in the park for a horn player. Yet in this performance, the tempos tended to drag somewhat and the outer movements could have used more sway in the rhythms and more joie de vivre in spirit.

Kahane pursued a different, more characteristic course in Mozart’s Symphony No. 39, with more pleasing results. Here, the tempos moved along briskly, with a very fast Menuetto that felt more like a scherzo, and the LACO’s playing was neat and light on its feet.