Three marvelous musicians, playing widely differing instruments, made beautiful music yesterday afternoon in Masur Auditorium of the National Institutes of Health.

A piano's keys are struck, a clarinet is blown and a viola is bowed. But with these instruments in the hands of Lee Luvisi, Richard Stoltzman and Walter Trampler, music by Mozart, Hindemith, Brahms and Schumann came out as if mechanical diversity was an advantage. Trios by Mozart and Schumann framed a sonata for viola and piano by Hindemith and one for clarinet and piano by Brahms.

If personal favoritism counts for anything, the E-flat Clarinet Sonata by Brahms, with Stoltzman and Luvisi, was not only the high point of the afternoon, but one of those times when everything you have always wanted to hear in a performance was gloriously laid out. Stoltzman controls dynamic shading to a degree rarely heard on the clarinet, matching it with the subtlest musical instinct. Luvisi, a superb artist in everything he touched, spread beauty through every phrase.

Mozart's late trio, K. 498, is one of those works in which, as he delighted in the resources of the then newly developed clarinet, he found new paths to formal perfection and expressive beauty. In it, as in Schumann's "Fairy Tales," the three players fulfilled the music's high aims.

Trampler and Luvisi played powerfully in the rather thankless later sonata of Hindemith. If only it had been the earlier one from Opus 11!