Adagio in G Minor, BWV 1001
A Look at the Structure, Part-Two
By: Heather DeRome, with thanks to Frank Koonce.
As Part-One discusses, the Adagio in G minor, BWV 1001, is in two main sections with the second section being transposed down a fourth from the opening. That is, the first nine measures move from G minor to D minor, and the last nine, repeated down a fourth, move from C minor back to G minor. See the part-one article, linked on the right, which examines where Bach made an exact transposition, where he ornamented, and the few places that were not transposed. Also linked on the right, is a video version of this article.

The present article discusses the short transition section from Bach’s arrival in D minor at measure 9 to where he takes off again from C minor at measure 14. In contrast to the outer sections, which are based on predictability, the harmonic writing in these five measures is definitely not what the listener is led to expect.

Both articles have a companion video, which is linked on the right.
These videos include played examples and so are also recommended.

I once read that in these measures Bach “meanders” from D minor over to C minor, and that got my goat, because I never think of Bach as meandering. So I had to go see for myself. I found that, no, the writing is actually very directed, and that Bach follows the customs and “rules” of his time; and, that really, his writing is right inside the box. However, that box has windows all around, and those windows are open. Bach’s creativity and artistry are endlessly fluid, but always with a firm grasp of the compositional practices that he assimilated while growing up. I see this section not as meandering, but as flowing like a river, and like a river with its twists and turns, and occasional rapids and eddies, it can only take you to one place. And in this case, that place is C minor!

The score below begins at measure 9, at the cadence on D minor. As is typical for Bach, after an important arrival, he immediately leaves again with a dominant-type chord of IV going to IV, and here he does that with viiº7 of G minor, going back to G minor at measure 10.

After in essence destabilizing the key of D minor, we are now ready to begin heading to C minor. Bach begins this by way of a circle of fifths with the dominant of G, followed by the dominant of C minor.

In measure 11, the circle of fifths continues with C minor, F minor, and B flat. (Take note of the tenor voice in the first two beats, with its ascending line D-E flat-F-G.) At the next downbeat, we arrive at the dominant of E flat, with a B flat 7 chord with the 7th, A flat, in the bass. This is rather unusual: Dissonant notes are not normally approached by leap, as is this A flat, after the previous bass-note, C (on beat one). And indeed here, that B flat chord with the dissonant bass may feel a little jarring. However, one may also hear that A flat as part of the previously mentioned tenor voice: D-E flat-F-G,- and then A flat. So, essentially, Bach continues the tenor voice with an octave displacement, moving the A flat below the bass C. Hearing it this way gives it a strong sense of forward motion and really does add intensity to the passage. Following this, instead of resolving the A flat in the low voice, Bach uses his 32nd-note run to bring that dissonant note up, and into the soprano where it does resolve at measure 12, beat one, as expected, by falling to the third of an E flat chord.

In measure 12, Bach continues to strongly tonicize E flat. After that striking cadence, he uses a simple I-IV-V progression, and we are clearly lead to expect a perfect authentic cadence,1 settling on E flat.

However, we do not arrive on E flat as expected; instead, we have an A diminished chord: A/G flat/C/E flat––a puzzling chord indeed! Although the melody does have the expected E flat, the bass is a tritone away from the anticipated note, and the inner voices also come as a surprise. Now, A-diminished wants to go to B flat, but instead, this chord moves to B diminished. Everything here is unforeseen. ... And what of the fermata above this chord? This is the only fermata in the entire collection of Sonatas and Partitas, other than the ones at the ends of movements.

So what is this mystery chord with its fermata? With a perplexing chord like this, it often helps to look at it in terms of where it is going, rather than from where it came: In this case, the chord leads to a dominant of C minor; more precisely, viiº of C minor. If, without changing the actual pitches, the G flat were re-spelled enharmonically as F sharp, we could have A/F sharp/C/E flat, or F sharp diminished 7, the viiº7 of G. So our little progression sounds like Viiº of G, to viiº of C minor, to C minor at beat 3, which is similar to what Bach wrote in measure 10, with his short string of dominants. As for the spelling of the chord, one may say that it conforms to the harmony of the preceding measures, but that the chord itself functions according to where it is going.

This may also provide an explanation as to why Bach felt the need to include the fermata. Allowing that chord more time helps re-orient the listener (and performer) to what would otherwise be too much of abrupt turn of events.

Looking at the second half of measure 13, we see what may be argued as some of the most singular writing in the book. (It’s also very fun to play this passage.) As was mentioned in this video, Bach “meant business” here.

First, every chord-tone of the C minor is slid into, with F sharp going to G and D to E flat, B to C, and then F sharp again to G for the tonic 6/4 cadence on C minor. Also, looking at the bass at beat three, Bach moves by an augmented second, E flat to F sharp, adopting the rarely used harmonic-minor scale. Then, after the downbeat of beat four, everything is on off-beats. It’s definitely “jazzy.”

All of this unsettled rhythmic and harmonic writing is very spirited and has been propelling us forward towards the downbeat of measure 14. This was Bach’s design, since the D minor arrival at measure 9, to take us to C minor. Over the barline of measure 14, when we finally arrive, everything is suddenly calm, and Bach gives us a quiet and placid resting point on the single, solitary note C. And from here we may begin the journey back home to G minor, with the last eight measures mirroring the first eight measures.

[1]V-I, with the bass as Sol-Do and the melody as Si-Do-Ré-Do.

Copyright Koonce/DeRome, 2019. All rights reserved.