A most appealing first impression

“Sound Investment,” the Los Angeles Chamber Orchestra’s commissioning program, is paying off. This consortium of enlightened, contributing music lovers delivered its fourth work at the Alex Theatre on Saturday night, an ear-enticing one-movement symphony, “Fanfares and Laments,” by USC’s Donald Crockett.

As led by LACO music director Jeffrey Kahane, the 22-minute “Fanfares and Laments” makes an appealing first impression. With the angular proclamations at the outset, you instinctively know that an American composer is at work; the harmonies and rhetoric hark back to the mid-20th century world of Copland, Harris and friends.

Crockett consistently comes up with fresh voicings and distinctive punctuations from the mallet percussion instruments, along with an attractive theme that was tossed around the orchestra midway through and a beautiful, hazy string dissolve at the close.

(Next season, that provocative mix-master of all styles, Uri Caine, gets the commission.)

The whole evening casually went under the umbrella title of “Devil in the Details” -- which referred only to a single movement of a single work by Boccherini. His Symphony No. 6 carries the ominous subtitle “La Casa del Diavolo” (The Devil’s House), presumably meaning hell.

Yet there is something only vaguely sinister about the movement in question, a finale that adapts music from Gluck’s “Don Juan” into a whirlwind no more threatening than Vivaldi in a bad mood. The orchestra played smoothly and brilliantly on its feet without a conductor (in deference to period practices).

Kahane turned up later in the dual role of conductor-pianist in Mendelssohn’s Piano Concerto No. 2, a fairly taxing juggling act that might have resulted in a less neatly played solo part than what we usually get from this fine pianist. Musically, however, Kahane scored many points -- taking swift tempos, forcefully pointing out the accents, building shrewdly and expressively toward the central climax of the slow movement.

Afterward, wryly acknowledging an “absolutely shameless plug for next season,” Kahane played and conducted the famous “Elvira Madigan” slow movement from Mozart’s Piano Concerto No. 21, a handsome preview of his projected cycle of 23 Mozart piano concertos.