I’ve seen a bunch of these visual representations and enjoyed them all. This one is Bach’s famous Passacaglia and Fugue in C minor for organ, performed and visualized by Stephen Malinowski.
Life is too heavy sometimes. Enjoy this if you have a spare tax-free minute.
This piece is in two parts — a passacaglia, followed by a fugue. The passacaglia has a bass melody, constantly repeated, with variations appearing in the upper voices. You’ll hear the bass theme alone at first, then with the variations as the bass is repeated. There are twenty variations in all, each the same length.
Watch the purple line to follow the bass. At 4:00, the bass theme moves into the treble voice (the high one, in yellow), then lower again. The passacaglia starts to build to a close around 5:30.
The fugue itself starts at 7:20. Technically, this is a “double fugue” — one with two main subjects. Both fugue subjects are heard at the same time at the start. The bass theme is used as the first theme (in red). The green is not just ornamentation, but the fugue’s second subject. These two themes, plus the “counter theme” that accompanies the first repeat (the green line starting around 7:35), are the building blocks of the fugue.
One of the nice aspects of this visualization is that you can always find the bass theme visually — just look for the characteristic long bars. The trills at 11:22 announce that the thrilling conclusion is near.
There are plenty more of these visualization, if the mood strikes you.
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