> Along with that other great keyboard work of Bach's last years, ''The Art of Fugue,'' the six-voice ricercare is among the greatest achievements of Western European civilization, and like ''The Art of Fugue'' and ''The Well-Tempered Clavier'' (or Keyboard), it was intended for performance on any of the keyboard instruments that one could find at home -- harpsichord, clavichord, small portable organ or early piano. It goes well on all of them.
But if Frederick the Great finally listened to it, he would have heard it on one of his Silbermann pianofortes.