does the progression VII > III in minor mean you have modulated to the relative major key?

Question

Is this progression possible in a modal minor chord progression or does it immediately make the III chord the new tonic via an authentic cadence?

Answer 1

This ambiguity is an important feature of the i-III pairing of first and second themes in classical sonatas and baroque (and pre-baroque) overtures. The progression c-f-Bb-Eb, taken in isolation, can be heard as i-iv-VII-III in C minor or vi-ii-V-I in Eb major. Schoenberg's suggestion of "neutralization" (emphasizing the notes that are different between two keys) doesn't work well between relative keys as they have the same notes. Likewise, it can be hard to make the i sound like a tonic; the major key III can sound a lot like a tonic. Perhaps the raising of scale step 7 in minor keys is helpful; V-i sounds cadential but v-i doesn't (though it's a good progression.)

One reason (some books on music history make this suggestion but I cannot remember which ones) that i-III is used for contrast is that the composer has to work a bit to get the III to sound like a different key. Simple ii-V7-I cadences could still be iv-VII-III in the relative. Similarly, it's not as easy to make a C to G modulation sound convincing in C major; the half-cadence V7/V to V7 is identical to the V7 to I in the key of the dominant.

As suggested in Tim's comment, placing cadences at phrase endings helps; a piece starting with i-V-i or I-V-I doesn't sound like a cadence but if rhythmically emphasized, it does.

Answer 2

From just VII III... no.

You need more context.

In some kind of circle of fifths or other sequential passage, it doesn't necessarily make sense to label any descending fifth progression as a key change.

Length matters too. If it's brief, tonicization is the term. If it's longer, like a whole phrase or period, then a modulation may make sense. Technically, I think you want to ask if there is a cadence, a real cadence. If so, then modulation is a sensible analysis.

Another thing to consider is III VII also does the job of setting up a potential change of tonal center, with all the caveats above about the scope of the change. Examples are Handel's sarabande in D minor, HWV 437. Or, the passamezzo antio form. Both of those work with a type of contracting of i V and III VII in minor. In other words you don't need a authentic cadence like descending fifth, you can also have a half cadence like descending fourth, to suggest a tonic/dominant or dominant/tonic pair.

Answer 3

The VII-III occurs in almost all minor songs that contain more than only tonic, dominant and subdominant and very often they are part of a fifth-fall progression. In this case music theorists don‘t speak about a modulation unless the music is not remaining for a longer section in the relative major key and isn‘t cadencing there e.g. on a fermata or the end of a section separated by a double barline.

Answer 4

First off, we need to clarify the terminology. Thinking in C minor, I know a system where vii is B minor (though viiº - B dim - would be more likely), VII is B major, ♭VII is Bb major. And I know one where minor chords are notated with a - sign, C minor would be I- rather than i.

But I'm stuck with VII - III. Is this B major to E major? (If not, how WOULD you label this?)

See what I mean? A system that only allows diatonic chords falls down when we stray from the diatonic strait-jacket. And I'm afraid music DOES, all the time.

But I suspect you mean Bb to Eb. A visit to the tonic of the relative major, via its dominant.

Yes, there's an authentic cadence in Eb. Sort of, maybe. 'Cadence' is a structural idea, not just a pair of chords. This may be a case of 'pass Go, do not collect £200' or 'Just visiting'. Or the music may stick around the new tonal centre long enough to be considered a modulation.

And it's not really worth arguing over. Perhaps it modulates, perhaps it just passes through. And when it's a case of relative major and minor, music often moves fluidly between the two with no particular borderlines.