Xrhrft

I came across the following chord progression, which I really like:

The iii4/2 chord adds a lot to the progression in comparison to the following:

I'm sure you could wrap your head around these progressions--I am just sharing the images for reference. My question: is there a reason why the first progression is more satisfying the the second? I looked at the root movement in the two progressions, and the iii-vi features movement of a descending fifth, which should sound stronger than that of the falling fourth in the iii4/2-vi. That's about as far as my analysis goes. I understand this my reaction to the chord changes is somewhat subjective, but can you see any technical reason I find the first progression more compelling/satisfying?

I see at least two reasons:

1. Tonal music is really built on the contrast of consonance and dissonance; the inherent tension and release of that dichotomy is what moves tonal music forward. Your second progression only uses consonant major and minor triads, and so it lacks much tension. But your first progression includes a dissonant seventh chord that brings in tension and helps push the music towards its release on the vi triad.


2. Similar to the first point, the second progression is completely made up of root-position chords. Your first progression includes an inverted harmony (the iii42) that adds a new sound and therefore interest to the progression.

Two other comments based on your question:

1. If you're writing your first progression according to the "rules" of college-level music theory, note that chordal sevenths will almost always resolve down by step. As such, the D in the bass of your iii42 should resolve down by step to C, not down by leap to A.


2. If you're interested, play around with making the soprano pitch in m. 2 a G♯ instead of G♮. That makes this chord what we call a secondary dominant that will lead even more strongly to the vi chord.


3. 
   

   You say

   
   
   

   
   

   I looked at the root movement in the two progressions, and the iii-vi features movement of a descending fifth, which should sound stronger than that of the falling fourth in the iii4/2-vi.

   
   

   
   

Note that the root motion is still the same, because the roots of those two chords are still E and A, a descending fifth. It's the bass motion that changes when you change the inversion of that iii chord.

PS: If you really like this chord progression, check out the theme to the US version of "The Office" :-)