The New York Youth Symphony occupies a healthy middle ground between music education and the professional performing world. Its continuing commissioning program, moreover, forms a similar bridge for young composers, soliciting new works and providing them a public forum.
A concert Saturday afternoon at Avery Fisher Hall served both these functions - giving us a chance to hear a mass of talented young players and including in their program a new piece by Jeffrey E. Brooks. Called ''Section Gang,'' this brief work abjures the bow altogether. String players pluck energetically throughout; and, though this shifts the leading roles to brass and percussion, ''Section Gang'' seems unusually subdued given its potential for sonic fireworks. The music is metrically very uneven, and the Youth Symphony's players got through it honorably - counting beats for all they were worth but projecting the air of survivors rather than victors.
Indeed, much of this program seemed not to match the talents assembled to play it. In the Sibelius Second Symphony, strings and brass caught admirably the solemn festivity of the last movement, but elsewhere they seemed tentative, even confused, by this music's dark moods and asymmetrical phrasing. Likewise, Schumann's ''Rhenish'' Symphony burst forth exuberantly in the outer movements but plodded within.
The young conductor, David Alan Miller, kept the attention of his players throughout - his manner understated, assured - in a word, professional.