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16b Discussion - Defining modulation

Class discussion

Key signature vs. key

  • You don’t have to change key signatures to modulate. Think of a piece in sonata-allegro form: it will rapidly modulate during the development, but we don’t get a key signature change for each one.
  • Tonic defines key. Key signatures are shorthand for the benefit of the performer, they have nothing to do with the actual key

Key relationships

  • Each key has five closely related keys: the key with one more sharp, the key with one more flat, and the relative minor keys of all three.
    • Ex: the closely related keys to C major are F and G major + A, D, and E minor. The minor keys are relative to the major keys, which include C major and the keys one sharp and one flat in either direction.

Tonicization vs. modulation: How do we tell the difference?

  • Signaling is the same for both: look for accidentals, namely raised notes (ti in the temporary/new key, fi in the current key)
  • Placement: is the new key area happening at the end of a phrase or is it in the middle? Furthmore, what is around it? If we stay in the new key, we’ve modulated, but if it’s temporary it’s tonicization.
    • In the second example we listened to in class, we have a V/VI - VI progression to the first fermata. However, the chords after it are still in the key of I. This indicates that we haven’t changed keys. If we had, the following chords wouldn’t make as much sense in I because they’re actually in the key of VI
  • Ear training is vital. We talked about it a lot in class, but being able to follow do as it moves between keys will speed up the process of figuring out whether we’re tonicizing or modulating
    • Be aware that the actual look of the music can be deceiving. In the Chopin example we went over in class, he starts tonicizing Bb major. Since the example is in G minor, Bb major’s relative minor, putting in a V/III requires no accidentals. Hunting for accidentals is a good start for finding secondary dominants and/or modulations, but as with most theory things…it doesn’t always work

If it establishes the new key it’s a modulation. However, this requires multiple things: you have to have a cadence, and you have to stay in the new key. “Does the phrase feel solid and stable in a new key?” is a really subjective question, though, which is how arguments/debate arise.