Effect of voicing / bass note on function of 7sus4 chord

Question

First post here, hope everyone out there is well! I am currently learning/analyzing Dolphin Dance by Herbie Hancock and a tangent ensued.. I wound up going pretty deep on function of Sus chords. My general understanding is good, but a few particulars remain.

1. How important is it to the function of the chord that the root of the sus chord be in the bass? For example, will it dramatically alter the function of G7sus4 chord if I play an inversion with F, C, or, D in the bass? To me it seems like C would have the greatest effect on the function, considering that would be resolving to the one too early. My understanding is that 7sus4 chords function as an "in between" chord moving from ii-7 to V7... in this context, how do different voicings affect its function?

2. Also, any other contexts that a sus is used for?

Answer 1

Naturally it depends on context. A typical sus chord can be used in a traditional preparation, suspension, and resolution pattern found commonly in Beethovian-tradition tonal music. It can also be used in support of common-tone harmonies (e.g. if the chord before and after the G7sus4 also have a C note in them). Or you could use it to obfuscate the modality of a passage, since it has neither a minor nor major third.

On the other hand, G7sus4 is a special animal in that it is constructed completely of perfect fourths (D-G-C-F). As such it is a chord that works well in quartal harmony systems. A well-known example of a tune written only in fourths is the very beginning of the original Star Trek theme song. If you're looking for a jazz example, try Herbie Hancock's Maiden Voyage. Because chords of this kind are symmetrical, they tend to feel keyless and suspended in pitch-space, with only weak notions of cadence and completion.

If you are using the sus chord in a more traditional context, the voicing and inversion (choice of bass note) is very significant and changes the color and function of the chord significantly. As a quartal harmony the inversion barely matters in my opinion.