Sinfonia No. 3 in D major, BWV 789
D minor's conversation - three voices trading a single idea.
Sinfonia No. 3 in D minor opens with a subject that gets passed immediately between all three voices in close imitation, so that by measure four every part has stated the theme and the three-voice texture is fully established. This is a miniature fugal exposition compressed into a teaching piece - a preview of the larger fugal thinking Bach was developing in the Well-Tempered Clavier, which he completed just two years after the Sinfonias.
D minor's restless energy, familiar from the larger pieces Bach wrote in this key, gives the Sinfonia a sense of urgency that the C-major and C-minor pieces lack. The middle section moves through the relative major (F major) for a brief moment of brightening before the final return to D minor's tonic.
Track the subject through all three voices in order.
Mark in your score every entrance of the main subject - there are more than you might expect. Practice each entrance separately, then play through the piece listening only for those moments, letting everything else recede. This turns the piece from a texture into a conversation you can follow.
Before you practice.
01 What is the subject of Sinfonia No. 3?
A short, rising D-major figure that outlines the tonic triad with a rhythmic kick. It is introduced in the soprano and then answered in the other voices in a brief fugal exposition.
02 How hard is Sinfonia No. 3 compared to the two-part inventions?
Harder. Even the most complex two-part inventions only require one independent voice per hand; Sinfonia No. 3, like all sinfonias, requires the right hand to manage two voices at once, which is a significant additional challenge.
Keep all three voices distinct at the climactic moments.
The passages where all three voices move in similar rhythm are the hardest to balance - they tend to collapse into a single loud block. At 70% tempo, actively listen to make sure you can hear three separate lines even when they move together. Reduce the volume of whichever voice is dominating and rebuild from there.
