Composing a song in Cm with major chord substitutes?

Question

I am composing a song in Cm with a very basic chord progression of I-IV-I. So, normally, in Cm, that would be Cm7-Fm7-Cm7, but I am actually playing Cm7-F7-Cm7.First of all, why does this work? This mix & match of Major and Minor chords in a minor key. Secondly, the obvious transition from IV is to V (G7), and it's ok...but what other transitions could I go for? Maybe modulation to another key?

Answer 1

First things first.

Your Cm song featuring the progression, Cm7-F7-Cm7, IS in Cm, if you considered the fact that there are several C minors. If you look at the structure of a major scale, there are 3 minors on the 2d, 3rd, and 6th degree of any major scale pitch collection; each one can be used as a mode/key center, resolve to Cm.

So Cm can be the

2d mode of Bb (Dorian),

3rd mode of Ab (Phrygian),

6th mode of Eb (Aeolian).

Your project is Dorian Cm.

There are more parent scales/key structures that contain a Cm7, but starting with the major scale is the best start.