0

Here’s an excerpt from Beethoven’s piano sonata no. 5, second movement, measures 13-16, with my analysis in blue (key of Ab major, 2/4 time):

Beethoven Op. 10, No. 1, "Adagio Molto", mm. 13–16, with analysis

My question is about the notes and chords in the blue box. At first I thought it was a Neapolitan or augmented sixth chord, but it’s not. I’m very curious about the augmented first degrees (A naturals) on relatively strong beats. Is this just chromatic material or is there something functional happening here?

Aaron
  • 87,951
  • 13
  • 114
  • 294
Todd Wilcox
  • 56,603
  • 6
  • 119
  • 200

2 Answers2

2

The overall harmonic motion of the measure is from IV to ii6. The transition is made through the augmented triad rooted on 4 — in essence, the first A-natural is just an accented chromatic passing tone.1

IV moving to ii6 via IV+

However, the arrival on the ii chord is intensified by the presence of viio/ii (over the Db pedal tone), also in a relatively accented position.

Measure 14 harmonic analysis

1 This same chromatic motion between a major chord and its relative minor in first inversion forms the classic accompaniment of the song "Brazil" ("Aquarela do Brasil", Ary Barroso [1939]). I really like this progression and also mention it in How do I use augmented chords in my progressions?.

Aaron
  • 87,951
  • 13
  • 114
  • 294
  • Would that make the A naturals part of a iimaj7 (minor-major) chord? – Todd Wilcox Nov 15 '21 at 03:30
  • @ToddWilcox Would appreciate your feedback on whether my edit better explains. – Aaron Nov 15 '21 at 04:38
  • You can probably treat that A as a chromatic passing tone rather than part of an augmented chord (rarely the case). – lbbl59 Nov 15 '21 at 12:14
  • Very much so! I’ll give it a bit before accepting it. Thanks! I am thinking it’s a neat trick to make the ii chord what we hear when it’s on the weaker beats. Maybe that’s helped by the delayed Db and F at the beginning of the measure? – Todd Wilcox Nov 15 '21 at 12:18
  • 1
    In other words, "Is this just chromatic material or is there something functional happening here," Yes and yes. – Andy Bonner Nov 15 '21 at 13:24
  • 1
    @ToddWilcox That's very interesting about the delayed Db/F. Not only the delay, but being a dyad, it's inherently ambiguous, plus the Ab, being at the weakest part of the beat, is barely heard as part of the chord. – Aaron Nov 15 '21 at 15:20
  • I'd really, really love to know what LvB was thinking at this point in the composition. Might be technical, probably not. – Tim Nov 15 '21 at 18:03
  • @ToddWilcox A frivolous request, but if you're still considering accepting my answer, today would be great, because I'll earn a Winter Bash hat (Hi5 - 5 acceptances in one day). – Aaron Dec 15 '21 at 18:49
  • Sorry, I actually went through recently to check for questions where o hadn’t accepted an answer and somehow missed this one – Todd Wilcox Dec 15 '21 at 22:35
  • 1
    @ToddWilcox No worries. The kid in me is looking forward to my new hat. – Aaron Dec 15 '21 at 23:04
1

I agree that this is basically moving from IV to ii6. But instead of an augmented chord, I'd treat that A as a chromatic passing tone. If you look at the line, Beethoven didn't have any emphasis on that A. If he really wanted that to be a chord, he'd make it more apparent. An augmented chord is usually a rare case in the classical period based on how I was taught.

Haydn used it in one of his string quartets and that chord is made clear - strong beat + all notes of the chord are played.

lbbl59
  • 364
  • 1
  • 10
  • The only thing is there’s an A natural on the second beat and then another one half a beat later. While they are both short, there’s two of them and if they are just passing tones why couldn’t they just be flattened as normal? – Todd Wilcox Dec 15 '21 at 22:34
  • @ToddWilcox, Yes. There are two of them, but they are there for different reasons. The second A-natural is there because Beethoven needed to construct a diminished triad that resolves to the ii chord. So that chord has a function and must be constructed that way (in fact, if you change it to an A-flat, it doesn't sound as natural - or actually tonal. It would sound like a modal progression). The first A, as I mentioned, is just part of an ascending line. The sustained D-falt and F are more important than that short A, despite that it's on a strong beat. – lbbl59 Dec 16 '21 at 07:28
  • The progression would become IV-I-ii if you change the second A to A-flat. Compared to the original IV-vii/ii-ii progression, that one has a plagal movement IV-I. It's a valid progression but has less tendency to move to ii. – lbbl59 Dec 16 '21 at 07:41