Changing keys mid song.

[Cartz]

One thing that always stumped me is how I can change keys midsong or between songs. What connecting chords can I use to change keys? What is the theory behind this? I know one option to change up a key (from C to a D) I can use a VI7 (A7) as a connecting chord.

[Guni]

Hi Cartz,

Modulation is quite a huge topic but lemme try to give you some more ideas and techniques.

Direct Modulation

Modulation may occur directly from any diatonic chord (mostly the I chord)

eg: Cmaj7 G7 Cmaj7 Dmaj7 A7 Dmaj7


Using Subdominants

That's your A7 example in C which takes you to the key of D. But you can apply this to all other chords in C.

C7 (I7) leads to F; D7 (II7) leads to G; E7 (III7) leads to B; F7 (IV7 is a special case) but can lead to Bb; B7 leads to E.


Using Pivot Chords

Chords that function in the original key and in the new key

Cmaj7 G7 Cmaj7 Am7 D7 Gmaj7
The Am7 is the VI in C and the II in G.


what else ..... oh yeah

Transitional Modulation
ie step by step ......

Cmaj7 Dm7 G7 Cm7 F7 Bbm7 Eb7 Abmaj7
starting out from C major there are bunch of II-Vs that lead to the new tonal centre of Ab major

and last but not least:

Deceptive Modulation

A Dominant chord can also be resolved in a few different ways, eg down a half step. This is what this modulation uses.

Cmaj7 G7 Gbmaj7

or up a half

Cmaj7 G7 Abmaj7


Hope that helps

Guni