When Steve Reich and Musicians performed some of Reich's earlier works at the Pension Building Saturday night as part of the 9th Street Festival, the audience response was, in some ways, as predictable as the music. The ceaselessly repetitious patterns underlining "Drumming-Pt. I," "Music for 18 Musicians" and, to a lesser degree, "Octet" exerted a calming effect; listeners sat absorbed, often with their eyes closed, as overlapping waves of what has been called "trance music" washed past them.

The centerpiece of the performance, however, was the Washington premiere of "Tehillim," Reich's setting of the Psalms with Hebrew text. Scored for four voices and 17 musicians, this chamber version of "Tehillim," conducted by George Manahan, proved to be a far more stirring and variegated work, even when the use of microphones and the building's unfocused acoustics conspired against it. The text, beautifully sung by Rebecca Armstrong, Jane Bryden, Jay Clayton and Pamela Woods, provided a basis for extended melodies, shifting meters and expanded harmony. More important, though, "Tehillim" occasionally conveyed an exultant level of human expression that much of Reich's music has steadfastly resisted in the past.

The 9th Street Festival continues next Saturday with a five hour tribute to John Cage. --Mike Joyce National Musical Arts

There is something about the perfection of a chamber music group such as the National Musical Arts that makes you think that whatever it must do is on the vanguard.

There are lots of such groups around Washington, but this is one of the best.

It decided to make the spotlight of its concert Saturday night at the National Academy of Sciences the piano quintet with winds by Louis Spohr. He was one of the great figures of the 19th century and has been much displayed recently as a new and fresh figure to disclaim the importance of Beethoven and Brahms in that most mighty of chamber music eras.

The problem is that Spohr is not one of the all-time greats. He lived from 1784 to 1859. He lived through the great spans of the giants.

The person he must have influenced most decisively was Franz Schubert. The difference between Spohr and Schubert is a question of the greatness of the creator. Spohr's strength is the notion of a large-scale four-movement work for nothing but winds and piano. Structurally, he is a historic composer; but his ideas were more exciting than his achievements.

Spohr simply opened the notion of larger possibilities in musical history. What agony it must be to suggest them and then not to occupy them.

Other splendid items on the program: Vivaldi's trio sonata in G minor for flute, oboe and bass; Saint-Sae ns' tarantelle for flute, clarinet and piano, and -- by far most important -- some riveting Hungarian songs by Zoltan Koda'ly, the most eminent of modern Hungarian composers.

Except for Barto'k, Koda'ly would be the giant of Hungarian music. What a curse!