[Smt-talk] II6/4

[Olli Väisälä]

Eytan, thanks for reply. I will comment on the following:

>
> With regard to the Bach C-major Fugue (I haven't looked at the  
> other Bach
> examples), the usual progression would be of course IV6-I6/4 
> (passing)-II6/5
> (in terms of G major). It seems to me that in this case the "II6/4"  
> is a
> rather "accidental" result of an inner voice that descends from C  
> to G (the
> G "should have" arrived a quarter earlier).

To be sure, the progression under question, II6/4–(I6/4)–II6/5 (in  
which the 6/4s are preceded by 6/5 or 7/5 suspensions), certainly  
shares common features with IV6–(I6/4)–II6/5. However, I do not think  
we can dismiss the II6/4 as a merely "accidental" substitute of the  
latter. This is because the ^2 supported by the II6/4 can play a  
crucial role in upper-voice structure.

The C#-major Fugue (WTC I) illustrates this lucidly. As already shown  
by Schenker, the high points of the subject compose a ^3–^2–^1 mini- 
Urlinie, in which the ^2 is further elaborated by ^2–^1–^7 (m. 2).  
Now in certain permutations of the triple invertible counterpoint,  
the ^2 is supported by a II6/4, while the upper-voice pattern remains  
the same; see mm. 19–21 (in E# minor), mm. 25–27 (G# major) and 42–44  
(home key C# major). (In the first two cases, there is actually no  
II6/5, but the passing I6/4 leads directly to the "VII6/4".) Here it  
seems clear that the ^1 in the passing "I6/4" is not a note that  
"should have" arrived a quarter earlier, but a passing note between  
^2 and ^7.

(One might note that the II6/4 is followed by bass figuration  
momentarily forming II6 on a weak eighth-note. Nevertheless, I  
strongly suggest that the functional bass line is formed by the  
metrically accented notes, descending stepwise from the local ^6 to  
^3 in each case and producing the 6/4s.)

In these cases, the II6/4 is highlighted by placing the ^3–^2  
suspension in the highest voice. In my ears, this has an interesting  
connection to Mozart's "Ah, vous dirai-je, Maman" variations III and  
VII, in which a ^3–^2 suspension is similarly raised to the high  
register. Hence I am entertaining the idea that these related  
passages might be modelled on the basis of a similar voice-leading  
pattern, even though no literal II6/4 appears in the Mozart.  
According to this idea, the Mozart also contains a ^3–^2(^1^7)–^1 (E6– 
D6(C6B5)–C5) top-voice progression, challenging the original 5-line  
of the theme.

I understand this may seem far-fetched, but before you make your  
verdict I would like to add one more supporting contextual factor.  
Consider mm. 5–7 in Var. I. I do not know how you (Eytan and others)  
would tend to read this passage, but there are certainly several  
factors that support perceiving a prolongation of II in these  
measures (II –"I"–II6).  These factors include hypermeter, the slight  
tonicization of II, and unified design (although the new right-hand  
pattern already begins in m. 4). If we read a prolongation of II  
here, the higher ^3–^2(^1^7)–^1 line is also there. Now if we agree  
that a prolongation of II may underlie this passage (Var. 1), this  
might make it a bit more plausible to apply a related model to the  
corresponding passage of subsequent variations despite the failure of  
the II (II6/4) to materialize as such.

But, as mentioned, I would be grateful for additional related Mozart  
examples for gaining better perspective for these considerations.

Olli Väisälä
Sibelius Academy
University of the Arts Helsinki
ovaisala at siba.fi