It wasn't supposed to happen this way, but the Contemporary Music Forum's evening of American music Thursday at the Corcoran Gallery became a tribute to Robert Parris, composer, George Washington University professor and occasional critic for The Washington Post during the '70s. Parris died Dec. 5; before then, the premiere of his "Nocturnes Book II" had already been scheduled as part of this very full concert.

In this piece for five players (conducted here by William Wright), Parris explored theatrical ideas about foreground and background: The viola and cello often painted two-dimensional backdrops while the clarinet or percussion seemed like actors out front.

The 20-minute work opened delicately, with impish bass clarinet phrases, a wiry viola tune and a rumble from the timpani. This coalesced into a mostly abstract sound world, where audible touch points--such as unexpected percussion effects--guided the listener. In the smiling second movement, the bass clarinet led off again, this time against a rhythmically jaunty bass line. A martial third movement darkened the mood, cleared by a spirited finale.

Another premiere on the program, billed as the "final version" of Andrew Earle Simpson's "Nebula," is a thick, Brahmsian clarinet quartet, where each instrument gets a strong voice and keeps the restless forward motion rolling. Like the Parris work, it gave the musicians plenty of trouble; one suspected a crack performance would yield more from the score.

Soprano Pamela Jordan sang two short song cycles. The first, "Evening" by Harvard undergraduate Christopher Trapani, showed a fine understanding of poems by Anna Akhmatova, although the vocal writing was often awkward. Jordan had no problems with Juliana Hall's "Syllables of Velvet, Sentences of Plush," based on letters by Emily Dickinson, seven songs with colorful piano accompaniment.

William Wright, in his other role as solo clarinetist, brought wit and warmth to Elliott Carter's "GRA."