Look at the text! Setting “Adam’s fall” to a descending diminished fifth in the bass is typical Bach chorale technique (see Heinrich Poos: “Der Choralsatz als musikalisches Kunstwerk”, in Musik-Konzepte 87, which focuses on crucifiction representations).

As to whether or not to identify it as a named, functional chord, or as a passing voice leading, I would incline to the former, due to both text and metric position, but emphasize both its novelty and the thoroughly unobjectionable voice leading.

My primary concern with this particular example is not the voice leading, which is is logical in any context, but rather the pedagogical ramifications of showing a group of second semester theory students a non-dominant Mm7 in anticipation of a future lecture on secondary function.

Thanks for the heads up on the article, and the note about the role of the descending diminished fifth in crucifixion settings. I’m not at home right now, but I don’t believe that Turek included the text in his example. I’ll have to check my copy of the Bach when I get a chance.

I agree with you, Mark. Until the students are good at recognizing dominant sevenths and thinking “= V7 of something” these exceptions should not be included. I would wait until mode mixture is taught, or even make a separate section on non-dominant Mm7 chords (IV7, VII7, bII7, etc.). It could also be a good subtopic of augmented sixth chords, since those often deliberately take the dominant seventh sound and resolve it differently.

I agree with Scott. Even though I teach modal mixture before I teach applied dominants, I would still withhold exceptional examples like this until students firmly grasp both modal mixture and tonicization.

I would disagree, however, with Scott’s assessment of bIIMm7 and augmented-sixth chords as not having dominant function. While there is still some debate on this matter, many theorists understand augmented sixths and tritone substitution as types of altered dominants. Further, as used in barbershop harmony and occasionally in 19th-century chromatic harmony, the Mm7 built on scale degree 4 is a kind of augmented-sixth chord. (See Daniel Harrison’s article “Supplement to the Theory of Augmented-Sixth Chords,” Music Theory Spectrum 17.)

In the Bach example, however, the IV7 is certainly not a dominant-function chord. To “correct” Bach’s use of modal mixture by either lowering scale degree 6 or raising scale degree 3 in the chord would make it sound ridiculous. What intrigues me is the question of whether 1) Bach decided to use the tritone leap in the bass first, which forced the bass to rise through the leading tone to the tonic, rather than descending to the dominant and leaping to the tonic, or 2) Bach wanted to use a stepwise ascent to weaken the motion to tonic at this premature juncture (two chords before the actual cadence) forcing the use of raised scale degree 6 to avoid an awkward augmented second.

I’ve gotta agree with those who say this example should be treated with caution so as to avoid confusion with secondary dominants.

Love the blog - I’m gonna link to it.

WF

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