Self-confidence is a compelling trait, and pianist Natan Brand, who performed at the Phillips Collection Sunday, exudes it. This was Brand's second appearance there this season. Six weeks ago, at the first recital, a piano string broke and, although he finished the program, it was under less than ideal conditions.

Sunday it was different. The piano held up through a barrage of thundering climaxes and, indeed, sounded more reasonant and evenly voiced than usual. Brand, working at two titans of the repertoire, Schumann's "Kreisleriana" and Mussorgsky's "Pictures at an Exhibition," was in excellent form, and the concert, a little shorter than most, was exactly the right length for a spring afternoon.

Brand approaches the piano purposefully. He has made up his mind about what he wants to do and he brooks no delay in getting at it. This decisiveness did not prevent him from lingering over the dreamy adagios of the Schumann, however, or from ensuring that the inner voices would be given their due weight and emphasis.

His Mussorgsky was a panorama of colorful images, molded with rhythmic flexibility, energy and a marvelous momentum. Brand is capable both of communicating powerful ideas and of displaying flashy brillance, and he is blessed with the sense to known which is appropriate when. Even found its proper place in both the Schumann and the Mussorgsky and made for an unusually satisfying afternoon.