Here is an excerpt from the Preludio of Bach’s E major Partita for solo violin.
If you were composing a free piano arrangement of this passage, how would you go about it? Rachmaninoff went about it by writing what is, in my opinion, one of the most delicious passages in Rachmaninoff’s oeuvre, and that’s saying a lot. The excerpt below if from Rachmaninoff’s arrangement of Bach’s Preludio. (He created a suite which includes arrangements of the Gavotte and Gigue from the same partita.) The fact that this harmonic progression is un-Bachian doesn’t matter, for this is Rachmaninoff-Bach rather than Bach-Rachmaninoff. Rachmaninoff knew as much as anyone that one cannot improve Bach. Rachmaninoff took Bach and created something altogether different. He created something wild and wonderful!
The harmonies are wild and delicious! Pulling these measures out of their surrounding context does something of a disservice, for Rachmaninoff has set us listeners up for these delightful harmonies. Beginning in measure 98, the music alternates between only two structural harmonies: tonic and dominant. Measures 102 to 105 make up what is essentially a prolonged four-measure dominant seventh chord (with a couple neighbor #viio chords in 102 and 103, and a few quick passing chords in m.104). The rate of harmonic change then undergoes a radical shift from one chord over four measures to one chord every eighth note. Here is the harmonic rhythm, beginning with measure 102:
I love the minor Neapolitan chord in root position at Chord #6. I wonder what the driving force behind Rachmaninoff’s decision to add the Bb to the previous major Neapolitan chord. Did he feel the need to keep the one-chord-per-eighth harmonic rhythm that had been established, requiring that the major Neapolitan be changed in some way? Or was it a voice-leading decision? Did he like the fact that the minor Neapolitan had zero common tones with the V43 that follows? The B-natural of the major Neapolitan would have been a common tone. With the passing F# in Bach’s melody, movement into the V43 is by half-step in every voice. Or perhaps he simply inserted the minor Neapolitan for it’s wild chromaticism—a minor triad in root position moving to a major-minor seventh chord whose root is a tritone away. (There is only one instance of this progression in typical functional harmony that I can think of—a minor ii chord in a major key moving to a Ger+6 chord, the latter chord being an enharmonically spelled version of the V7, of course.)
At any rate, I suspect that Rachmaninoff had all of these considerations, and perhaps others, in mind when he chose the minor Neapolitan.
More on Rachmaninoff’s voice leading. I have always thought that Rachmaninoff’s music gets short-shrifted by many who consider that the seemingly superfluous barrage of notes on the musical surface hides a lack of depth beneath that surface. To the contrary, it has always been my opinion that Rachmaninoff’s piano music is quite orchestrally composed, with contrapuntal lines pervading the texture at many levels. One can easily imagine an oboe playing an inner line here, a cello playing a longer line there, and so forth. While there may be better examples in Rachmaninoff’s oeuvre to show what I’m talking about (a great example being the Eb major prelude from the Op.23 set, perhaps the subject of a future blog post), we can see his careful voice-leading even here. Below is the same passage above, but with Bach’s original notes stripped (except on the couple occasions when Bach’s notes connect with Rachmaninoff’s voice leading, as in the A at Chord #9).
From chords 5 to 8 the bass and upper voices are linked, running in parallel motion. From chords 11 to 16, the two upper voice are more linked, with parallel rising lines, while the bass and tenor voices are linked in a kind of sequence—a sequence that might help explain Chord #11. Perhaps Rachmaninoff retrofitted the “fourth-seventh” interval pattern at Chords #13-14 back onto Chords #11-12. This might help explain the apparent VI42 chord, which does not function as a typical seventh chord. A better explanation might be to ignore the D-natural as a harmonic component, since it belongs to that embellishing chromatic rising line. All other seventh chords have properly resolving sevenths (though the resolution of the seventh of the ii7 chord (A in the tenor) is transferred to the bass.
All things considered, this is Rachmaninoff at his most delicious.
As always, comments are welcomed.