Johann Sebastian Bach

Not to be confused with an earlier piece in the same key and going by the same title (BWV 944, ca. 1708), J.S. Bach's Fantasia and Fugue in A minor for harpsichord (or perhaps clavichord), BWV 904, is an early Leipzig-period work probably composed ca. 1725. The fantasia opens with a dramatic, thickly chordal phrase, built upon a descending bass line; this turns out to be a kind of informal refrain theme between statements of which can be heard intertwining contrapuntal passages much like those usually found in the episodes of a fugue. The fugue itself is really a double fugue: the first subject -- a long, winding idea with nearly as many spaces as notes -- is put through the full expository works but is then cast aside in favor of a new subject -- this one pungently chromatic, steadily dripping downwards. Although one would never at first imagine it, these two seemingly incompatible musical ideas (the one absolutely diatonic and full of rhythmic holes, the other absolutely chromatic and rhythmically solid) were contrived from the start to fit together like a jigsaw puzzle; Bach demonstrates this in vintage fashion throughout the final third of the piece.