The fifth installment of the Settling Scores
In the chapter concerning “Bach the clavier player,” Forkel records that
“He even went so far, when he was in a cheerful humor and in the full consciousness of his powers, as to add extempore to three single parts a fourth part, and thus to make a quartet out of a trio.” [trans. in The New Bach Reader, p. 435; cf. C.P.E.'s letter in ibid, p. 397]And he repeats it in the chapter concerning “Bach’s character”:
“If he was in a cheerful mood and knew that the composer of the piece, if he happened to be present, would not take it amiss, he used, as we have said above, to make extempore, either out of the figured bass a new trio, or of three single parts a quartet. These, however, are really the only cases in which he proved to others how strong he was.” [Ibid., p. 460]Maybe there is some basis in fact to this story—even if it was only a single occasion—but it seems to me literally incredible otherwise. Forkel even acknowledged elsewhere that the sort of polyphony that allows the adding or reducing of parts has to be very specially constructed:
“In his compositions in four parts, you may sometimes even leave out the upper and lower part and still hear in the two middle parts an intelligible and pleasing music. [Only the two middle parts, Herr Forkel? An example would be nice....] But to produce such harmony, in which the single parts must be in the highest degree flexible and yielding towards each other if they are all to have a free and fluent melody, Bach made use of peculiar means, which had not been taught in the treatises of musical instruction in those times, but with which his great genius inspired him. These means consisted in the great liberty which he gave to the progress of the parts. He thereby transgressed in appearance, but not in reality, all the long-standing rules which, in his time, were held sacred.” [Ibid., p. 443]As an organist I am occasionally in a situation where a descant is added for the final verse of a hymn. Sometimes the descant line is printed in the hymnal on an extra stave above the four-part harmony. What I notice invariably—because it is indeed inevitable (that word that dogged my previous post)—is that in order to give the descant line a musically-satisfying melody, it will at times borrow note-progressions from the alto or tenor (or even the soprano), creating intrusive parallel unisons or octaves. Really, the right way—if I may be so bold—to add a descant is to compose it as a counterpoint to the melody, and then write a harmonic background for those two lines together. There are many examples of this done well, but too often I’m playing the other type. And it beggars belief that a hypothetical trio by Forkel’s “composer of the piece, if he happened to be present” would accommodate an added fourth line with its own integrity while not making substantial alterations to the original parts. I have naively accepted this as literal truth for too long. No longer: two examples I recently noticed suggest to me that four voices was too many for Bach to shuffle around in his head. Heresy? Maybe so. But look at these:
1) strict canon: “Christe eleison” from the Missa in A, BWV 234
I love this movement. For years I have used it on the very first day of Theory I, when students generally have no theoretical background, may only read one clef (if that), and may never have seen a full score. I throw it at them and ask them to observe: What do you see? And there’s much to be seen. It is a strict canon beginning with the bass soloist, and with ensuing entries in the tenor, alto, soprano, and finally two flutes in unison—each of these entries a perfect fourth higher than the last, and with the sustained harmonies in the strings never really relaxing into anything that feels like a resolution. Even the apparently simple question “What key is this in?” defies a simple answer. Also interesting is that the canonic line echoes its opening arpeggio (and more) twice even as the voices accumulate, so that the arpeggio occurs not just five but nine times, as if in stretto. (This is partially illustrated below, but if you’re curious you’ll save time just looking up the movement yourself. Good stuff.)
One day, sitting in the Subaru service department with the NBA Kritischer Bericht at hand—as you do—I was killing time looking at the variant readings for this movement. The report documented a series of systematic corrections in the autograph, commenting merely (and I paraphrase) “the corrections in bb. 80, 82, and 85 are related: Bach altered his conception after the fact, as the fourth canonic phrase initially began with a leap of a fourth.” [p.27] Each note circled below (the autograph score on the left, the NBA text on the right) was originally a fourth lower in the autograph.
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| Composite of BWV 234/i; SOURCES: (left) cropped scan of autograph score f. 3v (bb. 75-85) from ULB Darmstadt scan; (right) scan of Barenreiter TP 266 (off-print of NBA Ser. II Bd. 2), p. 11 (bb. 80-85); for both, I have added the red circles. |
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| SOURCE: cropped scan of Barenreiter TP 266 (off-print of NBA Ser. II Bd. 2), p. 11 (bb. 83-85) |
The NBA does not go on to explain why Bach would have made the changes. Bar 85 makes the reason clear: the A in the alto (the pick-up to canonic phrase “4”) was originally an E, but the leap up from E to A would cause parallel fifths with the tenor leap from A to D. This became an issue only when he wrote the fifth canonic phrase, but apparently he didn’t notice it in b. 82, so had to go back to fix it there; the retrospective change in b. 80 was only necessary to preserve the strict canon, and was thus presumably the last to be made. The lesson here? Bach could juggle a number of voices in his head as he constructed the canon, but clearly had to get it down on paper to get it right once too many voices had accumulated. In other words, he had not conceived phrase 5 when he first notated phrase 3.
2) permutation fugue: chorus Himmelskönig, sei willkommen, BWV 182/ii
This is a similar example—this time more complicated because the lines had to work as invertible counterpoint rather than just a canon. Arthur Mendel discussed this example in a 1960 Musical Quarterly article; his point was really just that an autograph that Spitta had taken to be a fair copy was really a composing score, as the types of corrections were not copying errors but rather directly related to the substance of the counterpoint:
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| Composite of BWV 182/ii bb. 1-5; SOURCES: (top) cropped scan of f. 1v of autograph score of BWV 182 from Bach Digital; (bottom) cropped scan of Mendel’s reconstruction of the first reading of these bars (Musical Quarterly (1960), his Ex. 1, p. 292); for both I have added the accolades on the left. |
“...we see that while there are no corrections in the first two measures, in measure 3 the last note in the soprano has been changed from an original a1 to d2, and there is a corresponding change in the alto in measure 4 and the tenor in measure 5. In the bass in measure 6 [not shown above], however, at the beginning of the second brace, there is no corresponding correction; here the corrected reading found in the other three voices was written in to begin with. If we look a little further, we can see that at the end of measure 4 not only the alto but also the soprano, and at the end of measure 5 not only the tenor but also the alto, have been corrected. But again in measure 6, the tenor bears no correction corresponding to those in the alto in measure 5 and in the soprano in measure 4.” [p. 292]and then reconstructs Bach’s compositional process:
“Bach starts out as follows, writing in the first brace the whole four measures of the soprano, then the rests plus three measures of the alto, then the rests plus two measures of the tenor, and finally the rests plus the subject in the bass. [This produces Mendel’s Ex. 1, given in the above composite.] But already on the fourth beat of the bass's subject-entrance (the first beat of measure 5) there occur consecutive octaves between bass and soprano. Apparently he next changed the soprano, inverting its motion to read d2-f#2 instead of f#2-d2.” [pp. 292f.]He then charts further changes to get from his putative original to the eventual (I hesitate to say final with Bach) reading. He concludes
“It is surprising to find that in writing such a permutation fugue (he had already written several that we know, and the scheme remained a favorite one with him) he had not worked out the invertibility of his four melodic elements until he set pen to paper to write a score that is neat enough to have been taken by Spitta for a fair copy.” [p. 293]Granted, Bach was clearly very good at this. The anecdote transmitted by Forkel suggests a contrapuntal understanding of such profundity (being able to spontaneously convert a trio into a quartet by the addition of an extra line) that writing out such examples into fair copy would not be surprising at all. For too long I’ve taken the Forkel story at face value, but when I stop to think of it it really can’t be true. “Just kidding,” as my students sometimes say when corrected; maybe Forkel would say the same.
ADDENDUM 20 August 2017
In the course of my Bach cantata pilgrimage, I have run across an interesting example going the other way—something originally in five real parts (SATB with a descant) in which Bach later deleted the fifth part, and had to make only very minor adjustments in two spots for the four-part version: compare the closing chorale of BWV 12 with its later use in BWV 69.
ADDENDUM 28 November 2017
Then again, the seven-part scoring of the final chorale of BWV 70 more than amply demonstrates Bach’s ability to write integrated-yet-disposable lines. Even so, there were some small alterations to the inner parts when this harmonization was included as a four-part chorale as no. 347 of the Breitkopf edition of Bach's chorales (1784-1787). See NBA Ser. III, Bd. 2, Teil 2, where this chorale appears on p. 200.