The two halves of last night's concert by the Theater Chamber Players, heard in the Kennedy Center Terrace Theater, were worlds apart in idiom but united in the high level of beauty.

In the first half there were works by composers who had a kind of musical kinship in that each was involved in brief, often disjunct writing, seeking distillations of sound for differing reasons. Ton de Kruyf, one of the leading younger Dutch composers, began the evening with a pas de deux for flute and piano. The highly ingenious music offers the two instruments in brief, bright dialogue in which wit is no stranger and fluent writing for both instruments a continuing element.

It was easy to sense De Kruyf's descent from the techniques of Anton Webern, whose Three Songs, Op. 18, and Six Bagatelles for string quartet followed. These are the epitome of Webernian conciseness, each song and bagatelle lasting usually less than a minute, each a model of economy of thought completely expressed. It was an inspired touch to perform the songs both before and after the bagatelles.

That Barbara Kolb found ways of melding her feeling for precise, fragile statements with an expressive romantic strain in Three Lullabies for guitar says much about her feeling for her godson, Robert Starobin, for whose guitarist-father, David, she wrote them. His performance, including humming in the final song, was exquisite.

David Del Tredici had a different vision, when he set James Joyce's "I Hear an Army," from that which inspired Eugene Goossens and Samuel Barber. Del Tredici seized on the terror of the poem and surrounded the verses with string quartet writing that skitters and frightens. The vocal writing, nearly as disjunct as that of Webern, is vivid in its depiction of the mood of the text.

Turning from these works to four songs and the Clarinet Quintet of Mozart was to enter a realm of perfection of another kind. It must suffice to say that the evening's performances by pianist, Dina Koston, soprano Phyllis Bryn-Julson, flutist William Montgomery, clarinetist Loren Kitt and the Washington Quartet, conducted by Peter Bay, were ideal. The program is being repeated tonight.