What chord is made of the following notes: F♯/G♭3, B3, D4, F4?

Question

I have a chord with the following notes:

F♯/G♭3, (G3,) B3, D4, F4

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This chord sounds to me like a harmonically dense G dominant seventh. However, I only tentatively added the note G to this in hopes to better rationalize the chord—which makes G a root that could otherwise be missing; I don't hear a significant difference when it is there and when it isn't.

The chords in this phrase are as follows: C Major, this chord, C Major (♯9). C Major, D suspended 4th, then D Major.

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What is this chord? G dominant 7th add diminished 8th? How do I spell the notes? (given that there is likely some kind of cross-relation.) Does it matter whether or not the note G natural is there?

Answer 1

I would assume (had I been sight reading this cluster) that it's G7 (GBDF) over an F# or Gb bass line. As mentioned above, on has to have context to be sure. If a whole note GBDF is written above the notes (G,Gb,F,E,Eb,D) with note values distributed to fill the measure as one wishes, this is just a G7 over a chromatically descending bass which isn't unusual.

Answer 2

I don't think there's any justification for adding a 'virtual' G. You really need to give some context. But, if you want a guess as to what it COULD be as a stand-alone, maybe be a B minor triad with an added b5.

Answer 3

If there's a B and an F in it, and it's preceded and followed by a C major, then it's almost certainly a G7 or something closely related (like a Bdim). The bass note could just be some kind of passing tone. How does it resolve? (How is the following C voiced?)

If I were writing a chord chart I think it'd be simplest just to call it something like Bdim/Gb, rather than try to describe the bass note as an alternation.