Measures 1 to 5:

• The flute and violin present the thematic material on which the movement is based in two voices.
• The harpsichord accompanies the soloists.
• We remain in the key of B minor.
• We mark the blue motif with blue squares.

Measures 5 to 10:

• The harpsichord assumes the role of soloist with the blue motif and develops the red motif in dialogue with the flute and violin.
• The flute and violin repeat the blue motif.
• We modulate to D major.

Measures 10 to 14:

• The harpsichord returns to its role as an accompanist.
• The thematic material of the first section is repeated, this time in D major.
• It is now the flute's turn to be imitated by the violin.

This is the formal structure of this movement. The thematic material in the first measures plays a role similar to that of a ritornello (blue squares), repeating in different keys and alternating with development sections (green squares). It is only in the development parts that the harpsichord plays as a soloist.

Measures 14 to 20:

• The harpsichord takes on the soloist role again.
• The blue and red motifs are transformed by inversion (dashed boxes).
• We now modulate to F# minor.

Measures 20 to 24:

The melodic material from the first bars, now n F# minor.

Measures 24 to 30:

• We modulate to E minor.
• We point out the red and blue motifs.

Measures 30 to 34:

• Modulation to G major.
• The flute and violin begin with the red motif but end with the blue.
• The harpsichord accompanies.

Measures 34 to 40:

• Back to B minor.
• We point out the blue motif in its original and inverted version and the red motif inverted.

Measures 40 to 45:

• Bach presents an additional development section.
• He uses the red motif in its original and inverted version.

Measures 45 to 49:

Recapitulation of the first bars to conclude.

Complete Movement

Constance Schoepflin (flute), Roxana Pavel Goldstein (violin), Matthew Ganong (harpsichord), Advent Chamber Orchestra (orchestra)
EFF Open Audio License