INSTITUTE ORCHESTRA PLAYS AT BOWL

The Los Angeles Philharmonic Institute Orchestra is of necessity a protean thing. Personnel changes from season to season are probably close to total, and the orchestra is led and rehearsed each summer by a varied cast of conductors.

Sunday at Hollywood Bowl, the playing of the sixth Institute Orchestra steadily improved throughout the evening. That may reflect growing confidence, adaptation to Bowl acoustics or attitudes toward different leaders, as well as the technical challenge of the music at hand.

Lukas Foss, one of the institute’s two directors for 1987, gave the young musicians thorough exposure to the currently popular cheerleading style of conducting. Working without score or baton, he stomped, hopped and waved, strutted like a berserk marionette and shook his fists dramatically in behalf of Tchaikovsky’s “Pathetique” Symphony.

His charges loved it, to judge from their demonstration at the end. The musical evidence, however, was less conclusive. The always ardent playing made striking gains in balance and intonation over earlier efforts, but cohesion and clarity were still lacking.

Institute fellow Clyde Mitchell, a Cal State Northridge alum now teaching at Cal State Long Beach, had charge of the orchestra for Bartok’s Third Piano Concerto. His handling of transitions was very deliberate, and intonation problems--particularly in the woodwinds--were extreme.

Mitchell did enforce supportive dynamics, and kept things generally abreast of his introspective soloist, Ursula Oppens. She was convincingly blithe in the perkier bits, helped by a very bright-sounding Falcone piano. But overall she seemed somewhat cool and distracted, though technically imperturbable.

Peter Rubardt drew Brahms’ “Academic Festival” Overture as his assignment. His straightforward industry was rewarded with enthusiasm, murky textures and out-of-tune violins.

A late addition to the agenda, Peter Ioannou led the National Anthem and a brass fanfare, “Stadt Wien” by Richard Strauss. He elicited an uneven, pell-mell performance.

Attendance: 6,843.