Johann Sebastian Bach (1685-1750) published his Duetto
(4) in 1739 at the end of his third book of
Clavier-Übung (Keyboard Practice), his monumental
compilation of works for the harpsichord. In essence,
the Duetto are two part inventions but with more
elaborate forms than most of the other works Bach
called Two Part Inventions. The Duetto No. 4 in A
minor, BWV 805, is the most complex of the four with
the most convoluted theme and the most elaborate
developments. The theme itself is long and hi...(+)
Johann Sebastian Bach (1685-1750) published his Duetto
(4) in 1739 at the end of his third book of
Clavier-Übung (Keyboard Practice), his monumental
compilation of works for the harpsichord. In essence,
the Duetto are two part inventions but with more
elaborate forms than most of the other works Bach
called Two Part Inventions. The Duetto No. 4 in A
minor, BWV 805, is the most complex of the four with
the most convoluted theme and the most elaborate
developments. The theme itself is long and highly
chromatic, presenting plenty of opportunities for
modulation. The theme is stated first by the left hand
alone and then in the right hand with detailed
counterpoints in the left hand. The first episode
starts in the minor with the opening of the theme, then
it moves to the major with the close of the theme. The
third statement of the theme is once again in the left
hand, but this time with counterpoints in the right
hand and the fourth statement is once again in the
right hand, but with new counterpoints in the left
hand. The second episode starts with fragments of the
theme in both hands and builds to a shattering climax
followed by a transition based on the opening of the
theme. The fifth statement of the theme is in the right
hand with counterpoints in the left and the sixth
statement is in the left hand with new counterpoints in
the right hand. The third and final episode fragments
both halves of the theme in both hands and builds to
the seventh and final return of the theme in both
hands, leading to a big final cadence.