I am learning about modes and trying to apply them on guitar over chord progressions, and I wanted to understand how exactly to know, when you hear some song, "ah, this song allows me to play Dorian in A over it, or Mixolydian in G over it", etc.
I found a method of determining this here, quote:
In the son.g Oye Como Va by Santana, we have the following chords: A Minor - D7 If you look at the Harmonized Major Scale, you'll see that this corresponds to a: ii - V, in the key of G Major. Since we're playing the G Major scale over a chord progression that's tonal center is A Minor, we know we are playing in A Dorian (The 2nd mode of G major is A Dorian).
Having this information, I tried to practice it, by applying it to other songs. I took for example "Fly Away" by Lenny Kravitz. The song has the chord progression:
A C G D
To my ears, it sounds like I should be focusing on the start of the progression which is A and C, since A sounds as tonal center of the progression (to my ears at least). So I opened up Harmonized Major Scale chart:
...and here is where I am stuck. If I look at the chart, the combination of A and C appears at:
- option A) "I III" in A, this would give A Ionian (?)
- option B) "II VII" in B, this means A Locrian (?)
- option C) "V VII" in D, so A Mixolydian (?)
- option D) "II IV" in G, so A Dorian.
I tried these assumptions and the A Dorian sounded really good (to my ears, subjective) on Fly Away. And this is where I get confused, because I feel like I chose the option totally randomly based on just occurrences in the harmonized major scale chart. So I guess the correct answer was: option D) with A Dorian, but why not the others too? Why are the other options wrong, did I misunderstood the method of identifying the right mode?
How do you know really know a mode fits in some key, when you see a chord progression?
Thank you.