Bach by popular demand…

Well, as requested, at any rate…

Here is an analysis of the first two measures of the B-flat major Prelude from WTC I.

Warning: this analysis breaks some of the rules (well, one in particular) of strict Westergaardian theory as expounded in ITT. In fact, it does so twice (at two distinct stages). Exercise: see if you can identify the rule that is broken, and give a convincing rationale for relaxing it.

1. The basic structure:

2. Segment the final two beats of the first span with: an incomplete neighbor in the bass, a complete neighbor in the soprano, a borrowing from the bass in the alto, and a rearticulated suspension in the tenor:

3. Anticipate the G in the soprano:

4. Borrow from these structural lines to create the texture of the passage:

5. Delay the fourth half-note:

6. Elaborate further (the operations being, I hope, clear):

7. Elaborate still further to obtain the passage as Bach gave it to us:

Happy New Year!

One Response to Bach by popular demand…

1. funkhauser says:

Excellent! Thank you, this is exactly what I’ve been looking for. I am very happy to see this analysis, as it agrees very well with what I hear in this piece.

Your analysis also reveals something I have believed for a long time–namely, in bass lines with a basic structure of 1 – 6 – 4 – 5, the 6 and 4 arise as neighbor tones to the 5. The 6 is an upper neighbor while the 4 is a lower neighbor.

It is very interesting to me to see the contrast between this analysis and the one given in the Part I, Ch. 2, Ex. 1 of “Structural Hearing” by Felix Salzer. Of course, Salzer uses a bizarre mixture of harmonic progression and linear progression in his analyses, but they are still of a largely Schenkerian/linear nature.

In his analysis of this piece, Salzer asserts that the Bb – G – Eb – C in the bass line is the result of an inversion of an ascending major second Bb – C to obtain a descending minor seventh, followed by a “filling in” by thirds to get Bb – G – Eb – C.

I personally like your analysis more, because I it seems more “structural” (i.e. new bass notes arise as neighbors to more fundamental notes). But I’d like to hear your thoughts on it. What is your reaction to Salzer’s analysis of the bass line? Why would you disagree, and why would you argue that your analysis is better?