There was a celebration of new American music at the Corcoran, most of it written to display the immense talents of oboist James Ostryniec. His is the kind of self-effacing virtuosity that calls attention to the music itself rather than to his superb performance. And there was much to praise in the works heard last night.

Lawrence Moss' "Unseen Leaves" is a haunting cantata for soprano, oboe and piano. Its electronic part began with all the brutality of Stockhausen's "Intensitat," but with vastly more interesting developments and a superimposed live soprano part that called for hissing, hushing, speaking and singing. All of these soprano Ruth Drucker did beautifully, with Arno Drucker at the piano and Ostryniec playing the oboe. Save for the inevitable amateur slide show and some unimaginative use of taped speech, "Unseen Leaves" is a remarkable achievement.

A "Pentagram" for oboe and electronic tape by Vladimir Ussachevsky recalled that pioneer's early works, with a humorous scherzo and a ravishing, almost romantic postlude. Joseph Julian's "Wave Canon" had the most fascinating electronic execution, with a single note from the oboe woven insistently into a distored, disturbing pattern as the live oboe itself murmured gently. Lawrence Singer's "Sensazione" was astounding in its cataloguing of new syntactic possibilities in the language of the English horn, but had little substance beyond that.

The one disappointment of the evening was the world premiere of Gordon Cyr's "The Siren Stream to the Outcast," for soprano, oboe and piano. Yet in this highly talented company, it only disappointed by comparison. The work did display Ostryniec's superhuman technique, pushing its sounds into a new language of microtones and whispers.

These concerts at the Corcoran, presented by the Contemporary Music Forum, are the most stimulating and entertaining way to keep up with the new and the very beautiful in music in Washington.