The Mudcat Café TM
Thread #85297   Message #1580365
Posted By: Don Firth
10-Oct-05 - 03:17 PM
Thread Name: Changing Keys in Middle Song: Best way?
Subject: RE: Changing Keys in Middle Song: Best way?
M Ted, the change you describe is not, strictly speaking, a key change. As long as the only chords you are using are C, F, G or G7 (primary chords) and Am, Dm, and Em, E, or E7, (relative minor, which, within the context of the key of C, would constitute "color" chords"). Tossing an out of scale passing tone into the tonic chord before moving to the subdominant doesn't, by itself, constitute a modulation or key change. To constitute a full-blown key change, you'd have to establish the F unequivocally as the new tonic. This is usually accomplished by also using a full Bb chord (subdominant of the key of F) very shortly thereafter and avoiding a G or G7 (which would lead you back to C) for a bit.

This sort of thing is, of course, highly debatable. For example, the first known use of a dominant seventh chord (which contains a diminished fifth, or the "Devil in Music," which, for some peculiar reason was frowned upon by the Church and forbidden in liturgical music) was by Monteverdi in a madrigal arrangement he did of sumer is icumen in. At the very end, in the penultimate beat during the final cadence, the interval between two of the voices was a diminished 5th. If you take a vertical slice out of the score at that point, you have a dominant 7th chord. People were scandalized and horrified. Someone commented, "The human ear will never grow to tolerate such dissonance!" This interval is now found, of course, in every dominant 7th chord, and it's the famous "flatted 5th" of jazz. It's what gives a dominant 7th chord its "drop the other shoe" effect. Anyway, ever since then, musicologists have argued as to whether this was actually a dominant 7th chord, or did the offending interval come as a result of a passing tone in a polyphonic madrigal rather than harmonic song form? What did Monteverdi really have in mind?

Lotsa fun! Tends to keep musicologists safely off the streets.

Don Firth