Sinfonia No. 15 in B minor
The final Sinfonia - and Bach's most searching.
Sinfonia No. 15 in B minor closes the set of fifteen three-part keyboard pieces Bach prepared around 1723, and its placement last is fitting: it is the most harmonically ambitious of the group, moving through remote key areas in a tight fugal argument that sounds simultaneously strict and improvisatory. B minor - the key Bach also chose for his great Mass and for many of the WTC's most inward pieces - carries a quality of austere introspection here.
The subject opens with a rising leap followed by a chromatic descent, a combination that generates maximum harmonic interest every time it returns. Bach works the three voices into stretto - overlapping entries where one voice enters before the previous one has finished - creating a density that rewards slow, attentive practice more than any amount of fast run-throughs.
Follow the subject through the web.
Mark every entry of the subject in your score with a pencil before you begin practicing. Then, as you work through the piece hands separately, track which voice is carrying the subject and which are free counterpoint. This awareness makes the stretto passages in the final third feel like a planned climax rather than a sudden tangle.
Before you practice.
01 What is 9/16 time and how should I feel it in BWV 801?
9/16 groups into three beats of three sixteenth notes each, giving it a lilting compound feel. Think of it as a slow triple meter with a gentle lilt rather than counting nine individual pulses.
02 Is Sinfonia No. 15 harder than Sinfonia No. 9?
Both are intermediate, but BWV 801's compound meter adds a rhythmic layer that can feel unfamiliar. Once the pulse is internalized the three-voice writing is comparable in difficulty to the other sinfonias.
Stretto rewards patience.
The stretto entries near the end (where subjects overlap in all three voices within two bars) are the technical crux of the piece. Loop that passage at 40% tempo until each entry is audibly distinct - the moment you can hear all three voices as separate threads, the rest of the Sinfonia falls into place.
