Church Modes

The modes (church modes or Gregorian modes) is here presented. To ease notation we start at the major scale in c and ascend through the modes from this key. We can play these scales using only the white keys on a piano. Some very interesting interplay exists between the different modes and the chord and function that belongs to that mode.

The chord presented along the given mode has at least 4 tones.

I Ionian (major scale)

The scale in the key of c is as follows

c d e f g a b

As guitar tabs

1:d1,e1,f2; 2:a1,b1,c2; 3:e1,f1,g1; 4:b1,c1,d1; 5:f1,g1,a1; 6:c1,d1,e1;

The chord is a major seventh, denoted Amaj^{7} or A^{\maj}. The arpeggio is as follows

c e g b

If we strip the seventh step and instead add the sixth step, in this case an a, we have the arpeggio

c e g a

And if we the move the a one octave down, we get an Am^{7}

II Dorian

The scale in the key of d is as follows

d e f g a b c

As guitar tabs

1:e1,f2,g2; 2:b1,c2,d2; 3:f1,g1,a2; 4:c1,d1,e2; 5:g1,a1,b2; 6:d1,e1,f2;

The chord is a minor seventh, the arpeggio is

d f a c

In the key of d noted as Dm^{7}. This chord can be extended with a sixth, compared to natural minor the sixth step in Dorian mode is raised one semi tone. The arpeggio for Dm^{6} is

d f a b c

Omitting the last c and moving the sixth (the b) one octave down, we get a Bm^{7\b5} chord (the Locrian mode) with the arpeggio

b d f a

III Phrygian

The phrygian mode is pretty much as natural minor, though with a lowered second sted. In the key of e we get

e f g a b c d

As guitar tabs

1:c1,d1,e1; 2:g1,a1,b1; 3:d1,e1,f1; 4:a1,b1,c1; 5:e1,f1,g1;

This mode functions as a minor seventh. The four tone arpeggio for Em^{7} is

e g b d

IV Lydian

The Lydian mode is a major seventh. In the key of f we get

f g a b c d e

As guitar tabs

1:g1,a1,b1; 2:d1,e1,f1; 3:a1,b1,c1; 4:e1,f1,g1; 5:b1,c1,d1; 6:f#1,g1,a1;

As mentioned we this functions as a major seventh, denoted F^{\maj}, with the arpeggio

f a c e

V Mixolydian

The Mixolydian mode is a major mode, though it has a lowered seventh, the same seventh as a minor chord. In the key of g we get

g a b c d e f

As guitar tabs

1:a1,b1,c1; 2:e1,f1,g1; 3:b1,c1,d1; 4:f1,g1,a1; 5:c1,d1,e1; 6:g1,a1,b1;

The chord is named a dominant seventh chord, this is normally just noted as a superscript 7. Here we have G^{7} with the arpeggio

g b d f

Extending with the ninth step, that is an a, and removing the tonic, we have Bm^{7\b5} - the chord that belongs to the Locrian mode.

VI Aeolian (natural minor)

The scale in the key of a is as follows

a b c d e f g

Or in guitar tabs

1:b1,c1,d1; 2:f1,g1,a1; 3:c1,d1,e1; 4:g1,a1,b1; 5:d1,e1,f1; 6:a1,b1,c1;

The chord is a minor seventh, noted Am^{7}. The arpeggio is as follows

a c d g

As with all other minor seventh chords we can move the key node up one octave, treat the third as key node and obtain a major 6 chord. For C^{6} we get the arpeggio

c d g a

We can extend Am^{7} with the ninth step, that is the second step raised one octave. We get Am^{9} with the arpeggio

a c e g b

Doing the same trick as above we get the full five tone major sixth chord, that is the ninth step in the minor scale turns into the seventh step in the new major chord. We get the arpeggio

c e g a b

VII Locrian

The chord is a minor seventh with a diminished 5. This is sometimes called a half diminished chord. The scale in the key of b is

b c d e f g a

Or as guitar tabs

1:c1,d1,e1; 2:g1,a1,b1; 3:d1,e1,f1; 4:a1,b1,c1; 5:e1,f1,g1; 6:b1,c1,d1;

The chord is noted Bm^{7\b5} or B^{\dim7}. The arpeggio is

b d f a

Moving the key node one octave up we get a four tone Dm^{6}.