Each key signature has seven modes.
A mode, quite simply, is the act of playing a scale, but shifting the tonal center from the one. If I were to use the C major key signature, but play the scale starting and ending on an E, I would be playing a mode. Modes can be derived in two ways. First we will examine the relative method of deriving modes. We will then examine the parallel method of deriving modes.
The easiest way to think of modes is in a relative fashion. As stated before, each key signature contains seven. The diagram below lists the name of these modes next to the scale degree on the tonal center has been shifted.
1. Ionian (Major)
6. Aeolian (minor)
Let’s examine each one of these using the F Major key signature.
First I will derive the scale, then list the key signature, and finally list each mode.
Our key signature contains only a B♭.
Press Play to Hear the Scale
Scale notes are filled in with color.
Next, we have but to play the scale starting on different scale degrees.
Since I know my key signatures, I can just go through the alphabet applying flats when I know I need to. Below, our modes in this key signature are listed. The starting note of each is highlighted in yellow.
It is quite easy to find these in relativistic nature. You simply need to build a working knowledge of key signatures, and you’ll then know all of your modes.
Another approach that can be used is to examine these modes parallel to their major scales.
I’m going to use the C major scale to find each mode using the C major key signature. We will then compare those modes to their parallel major scales. By doing that, we will know how to alter our major scales in order to make them modes. Remember, Ionian is the same as major and Aeolian is the same is minor.
So, in order to make any given major scale the Dorian mode, we must flat the three and seven.
And in order to make any given major scale the Phrygian mode, we must flat the two, three, six and seven.
To make any given major scale the Lydian mode, we must sharp the four.
And in order to make any given major scale the Mixolydian mode, we must flat the seven.
To make any given major scale the Locrian mode, we must flat the two, three, five, six, and seven.
Below are shown all alterations:
Dorian: ♭3, ♭7
Phrygian: ♭2, ♭3, ♭6, ♭7
Locrian: ♭2, ♭3, ♭5, ♭6, ♭7
I encourage the student to play these modes, using chord progressions pertaining to the mode’s key signature. They’re lots of fun, and will add flavor to your playing it the process.