Do the following test and you will understand the modes.
Modes are just the different sounds of a scale being played against a chord or chord progression.
In the Key of C you have the following chords C, Dm, Em, F, G, Am, Bdim
You will need a looper or a recording device.
Since we are in the key of C we will use ONLY the C major scale.
Record into your looper a C chord. Play the C major scale in any order. You have Ionian sound
Record into your looper a Dm chord. Play the C major scale over it in any order. You have Dorian sound.
Record into your looper a Em chord. Play the C major scale over it in any order. You have Phrygian sound.
Record into your looper a F chord. Play the C major scale over it in any order. You have Lydian sound.
Record into your looper a G chord. Play the C major scale over it in any order. You have Mixolydian sound.
Record into your looper a Am chord. Play the C major scale over it in any order. You have Aeolian sound.
Record into your looper a Bdim chord. Play the C major scale over it in any order. You have Locrian sound.
It's important to note you don't have to play the scale in any order. A mode is simply the major scale played over certain chords that in turn produce a mood. like happy (Ionian) or dark (Aeolian)
For instance if you play the C major scale (in any order) over a C chord like above you will have the Ionian sound.
If you play the same C major scale (in any order) over a Am chord you will have the Aeolian Sound. Am is the sixth chord in the key of C.
It is important also to note that the Root chord in a progression (Root chord being the tonal center i.e. what sounds like home) also defines the mode.
So if the chord progression is C, Am, F, G and C sounds like home, you can play the C major scale over all the chords and it will maintain the C Ionian (happy) sound over all the chords because the C chord is what feels like home.
