It's been almost 50 years since the serial composer Milton Babbitt produced his infamous article "Who Cares If You Listen?" But not all of his works are inaccessible to the public. "Vision and Prayer" for soprano and tape, for example, employed Sprechstimme, a form of vocal expression halfway between song and speech. The technique can be hauntingly beautiful, and in "Vision and Prayer" it is combined with evocative timbres matched to specific vowels in Dylan Thomas's poems.

The piece was included in a concert at the Kennedy Center Terrace Theater on Saturday, where the Theater Chamber Players featured different instrumental combinations in a series of primarily 20th-century works.

Although soprano Phyllis Bryn-Julson underplayed the speech-song effect in "Vision and Prayer," her singing still captured the spirit of the work. Leon Fleisher directed a group of eight musicians in Edgar Varese's "Octandre" and Igor Stravinsky's Octet--two very different 1920s Paris compositions featuring flute, oboe, clarinet, bassoon, horn, trumpet, trombone and contrabass.

These pieces were performed a bit indolently, however, in that a necessary crispness was lacking in the trombones and the flute. Still, the bassoon and trumpet compensated: The scintillating musicianship provided animation and clarity. The most effective delivery came in Mozart's String Quartet in C, K. 465, in which all players sizzled with efficacy and verve.