Contrapunctus I from the Art of the Fugue

Contrapunctus I

The exposition

In the Contrapunctus I from the Art of the Fugue (Die Kunst der fuge BWV 1080) by J. S. Bach the subject appears in the alto:

The soprano answers with a tonal answer:

Although a tonal answer, it 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 b y c.
• Motive b is taken from the last four notes of the subject.
• Motive c could be considered the inversion by augmentation of motive b.
• Motive a will be used throughout the fugue. Melodically, it is related with the first notes of the answer.

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.