Contrapunctus I from the Art of the Fugue
The Contrapunctus I from the Art of the Fugue (Die Kunst der fuge BWV 1080) by J. S. Bach begins by presenting the subject in the alto:
The soprano answers with a tonal answer:
The tonal answer is in the key of A minor.
The counterpoint that goes with the answer has several interesting aspects:
- Notes in red are related to the subject as well as the motives a, b and c.
- Motive a is based on the first notes of the answer.
- Motive b is based on the last notes of the subject.
- Motive c is the inversion and augmentation of motive b.
The bass and tenor present voices 3 and 4:
- The subject played by the bass (measure 9) is accompanied by motive a in a kind of dialog between the soprano and alto voices. Motive b is also used.
- The answer is played by the tenor (measure 13) and the bass plays the same counterpoint used with the first answer (marked by a rectangle).
- A new motive d is played by the alto and the soprano. It is related with notes 4 to 6 of the subject.
The exposition ends in measure 17.