Chord Progressions

I haven't done a post about music theory for a while, so here is one about harmony. I've talked a lot about harmony, especially about how it is a problem for composers of contemporary music. Here is one of those posts.

But today, I want to talk about harmony in a more practical way, about chord progressions, to be specific. The Wikipedia article is worth looking at, though it is written from the point of view of popular music. The author seems to have very little knowledge of how classical musicians understand harmonic progressions as witnessed by the tiny last paragraph, "Chord progressions in classical music."

As understood by popular musicians, a chord progression is a kind of cyclical harmonic gesture that repeats. One song that is a pure example of this is "All Along the Watchtower" by Bob Dylan:

Here are the chords in that version. The most famous version is the one by Jimi Hendrix, who does it in A minor instead of the C# minor of the original:

What both versions share is a kind of floating, eternal quality that I think comes from the harmonic progression. This song is extremely focussed: there is no bridge, chorus, middle-eight, nothing except that harmonic progression and the words. In Dylan's version the only contrast is provided by the harmonica solos and in Hendrix' version by the guitar solo.

Here is the bass line which I am going to notate in A minor, not C# minor because, as Dylan capos his guitar on the 4th fret, from the guitarist's point of view, it feels as if you are in A minor! Actually, Hendrix' version doesn't quite sound in A minor as he seems to be tuned a semi-tone flat so it comes out in G# minor. I suppose it is possible he is playing in G# minor, I just kind of doubt it.

And that's it, the whole song just cycles back and forth between these three chords:

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What you hear is more complicated because of the rhythmic execution of the chords, but those are all the notes. In terms of harmonic analysis, the progression is i VII VI VII over and over (minor chords indicated with lower case Roman numerals, major by upper case). The "key" is actually the Aeolian mode on A. It is not the conventional A minor because there is no leading tone. Part of the floating quality comes from the fact that the chords move only by whole tones.

There is another song by Bob Dylan with a bit more complex and directed progression. These are the chords to the verses of "Lay Lady Lay":

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The bass player has a number of options, most logically either follow the chromatic line down, or play A, C#, G natural, B, which are the roots of the chords. Perhaps A, C#, D, B. And, of course, you can do different ones at different points. The harmonic analysis would go I iii VII ii. Here is the song:

The "bridge" or "middle-eight" as it is conventionally called, moves to the the dominant with this progression:

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The harmonic analysis would be V vi I.

In both these songs, conventional cadences are avoided as in all music of the "post-tonal" era that we are living in.

Well, I seem to have written a complete post and I haven't gotten anywhere near what I really wanted to talk about, which is chord or harmonic progressions in classical music! I guess I will save that for next time. In the meantime, to whet your appetite, here is a famous introduction to a string quartet by Mozart, nicknamed the "Dissonant" quartet because of the extreme chromaticism of the harmonies. In this recording, that introduction is the first 1'43 which is followed by a more conventional allegro: