One of the great names in the history of the piano was back on the Washington musical scene yesterday. The name is Schnabel, and the player was Karl Ulrich Schnabel, the pianist son of the celebrated Artur Schnabel. He played a duo piano concert--one piano, four hands--with Joan Rowland at the Phillips Collection.

It was no exaggeration to suggest that the collaboration quickly brought to mind the delectable piano duos of Mozart and Schubert that Schnabel recorded years ago with his father; there was the same dash and devil-may-care abandon. Artur Schnabel was the man, after all, who, when asked by a student what were his priorities at the keyboard, replied, "Well, to begin with, 'Safety last.' "

His son, now in his early seventies, is not the virtuoso his father was, but his playing is very much in that spirit.

Schnabel's and Rowland's Schubert and Mozart, in the program's first half, had the combination of spirit and jaunty elegance that one came to expect of a Schnabel concert. The performances of both the Schubert Introduction and Variations, Op. 82, No. 2, and the Mozart F Major Sonata, K. 497, were wonderful balances of clarity and spontaneity, as were the exultant outbursts of Mendelssohn's Allegro brillant and Dvorak's B major Slavonic Dance.

Also on the program was the American premiere of a work called "Gradatim ad Summum (Summit by Steps)" by the Canadian composer Diana McIntosh. She describes it as a work "in four main sections, each one culminated by a quiet plateau." Those "plateaus" are full of mysterious sounds created from playing on the strings directly with the fingers, with pins and with metal brushes. The effect of this is not really so avant-garde, because the sounds literally suggest the notion of sound at increasingly high altitudes.