# how do you find Roman Numerals out of voicings?

the author says "In measure 2, V7/IV has b9 in the lead, ...".

I guess then 1st chord of measure 2 is G-7, 2nd chord is 2nd inversion of I7 (V7/IV).

But this is a lot of guess work (to me),

1. contextually dominant is sought for,
2. 1st chord of measure 2 has G in the bass so it MAY be G something chord(if it is in root position)
3. target chord has F in the bass so it MAY be F something chord (again, if it is in root position)
4. b2 is good to be emphasized(in the lead) for more forward motion (but not a MUST, only recommended).

Based on above contextual information (which could easily be wrong), from voicings of G Bb C E Db, I7 could be assumed.

I wonder such guess work really becomes the basis of the RN analysis that is to be done further on, a common practice of RN analysis for all classical pieces also?

• Voicing isn't particularly relevant to Roman numeral analysis. In fact, the primary point of Roman numeral analysis is to relegate the voicing of chords to secondary status -- to call attention to the functional equivalence of differently voiced chords. It's not clear to me from the question why your uncertainty concerns voicing. For example, would you approach it differently if the second chord's D flat were in the left hand and the C natural in the right, or if its bass note were E or C instead of G? Can you clarify? Commented May 3 at 9:43
• What is the key signature in the example? Commented May 3 at 9:56
• @user1079505 we can infer that the piece is in C major from the fact that the second chord is identified as V7/IV and the B flat is given as an accidental. Commented May 3 at 10:00

RNA requires interpretation at times, but basic chord progressions tend to be well understood.

In the example presented, and with the understanding the larger passage is in C major, then the analysis is `ii7/IV V7/IV IV`. This is based on a couple of standard conventions: 1) chords are understood as "stacks of thirds", and 2) the basics of functional harmony.

`V-7`, for example, has no special functional meaning, but `ii7` is a core predominant. Since the following chord is C7 — the dominant of F — and G-7 is the `ii` chord in F (major), there really can't be any other interpretation of these three chords, unless there is some larger context that could change things.

how do you find Roman Numerals out of voicings?

To answer this question literally, you first determine the root of the chord. This involves rearranging the chord as a stack of thirds and identifying the lowest note in the stack. This can involve some guesswork but usually is pretty straightforward.

Then you identify the function of the chord from its form and context. This can more likely require inferences that might be considered "guesswork," but for the most part it involves identifying where the chord falls in any of a small number of common harmonic progressions. The dominant seventh chord is easy, though, because it is always a dominant (that which is known as tritone substitution is, in classical music, an augmented sixth chord, so it has the same shape as a dominant seventh chord enharmonically but is spelled differently).

If the chord does not have the harmonic function that is expected given its root, then it is generally "secondary harmony" so it is necessary to identify the scale degree that is the center of the secondary progression. That is also easy for the dominant seventh chord because it is always a perfect fifth below the root. It can be straightforward in general, but in harmonically complex pieces it can indeed require a good deal of insight, if not actual guesswork. But this is independent of the inversion.

Your thought process seems to skip the part about identifying the root, because your description begins by identifying the bass note and then wondering whether the chord is in root position. The first chord is plainly in root position; there's no need to consider "if" it is. Conversely, the second chord is plainly not in root position, so your first step should not be to look at the bass note but to find the root. If you stack in thirds, you have C, E, G, B♭, D♭ so the root is C.

• "Your thought process seems to skip the part about identifying the root" I agree to this. you said first chord is plainly in root position while second chord is not, do you discern by the second degree apart tones? what if there are tensions then? If a chord is in root position with tenstions, second degree apart tones will also be present.
– Sean
Commented May 10 at 2:33