Modal Scales

                Western tonal music is based off of 7 pitches within a given diatonic key.  Our key system can be based on either a major or minor tonality.  However, earlier in history there was a larger variety of tonalities called modes.  Modal key centers and scales still impact certain types of modern day music, so it is important to have an understanding of these scales.

In our previous lessons on scales, we discussed that a scale is a consecutive listing of the seven pitches within a diatonic key.  Modal scales are also a consecutive listing of seven pitches, but the melodic qualities of their intervals extend beyond the normal diatonic keys.  There are seven different types of modes, and they are derived from the original plus the six displacements of a major scale or key.  The first mode (Ionian) is identical to major.  The second mode is derived by maintaining a major key signature, but starting and ending the scale on the second scale degree.  This is what I mean by displacement.  The start and end point of the scale is displaced by one step.  With the third mode, the scale is displaced by two steps, and so on. 

The names of the seven modes are Ionian, Dorian, Phrygian, Lydian, Mixolydian, Aeolian and Locrian.  Within the video I supply a slide that shows the whole and half step sequence for each scale. 

          

The idea of displacement described above can be used to derive the pitches of any of these scales.  We only need to remember the number of the mode according to the order I listed above.  We can then relate that to a corresponding major key signature.  For example, an F Lydian scale would be an F scale with the key signature of C major because Lydian is the fourth mode and F is the fourth scale degree of C major. 

Another way to derive the pitches of the modal scales is to remember their differences in comparison to major or minor scales.  Ionian is identical to a major scale.  Dorian is similar to a natural minor scale aside from a raised 6^th.  Phrygian is similar to a natural minor scale aside from a lowered 2^nd.  Lydian is similar to a major scale aside from a raised 4^th.  Mixolydian is similar to a major scale aside from a lowered 7^th.  Aeolian is identical to a natural minor scale.  Locrian is similar to a natural minor scale aside from a lowered 2^nd and 5^th. 

There are many modern day musical applications for modes.  Some styles of music utilize a modal key center instead of a major or minor one.  Also, jazz improvisation relies heavily on the use of modal scales.  Many chords can be associated with specific modal scales that will provide the optimal pitches to use while improvising over that chord.  Finally, composers can use modes to express melodic motifs that go beyond the expressive confines of major or minor.  All of these reasons bring validity to the study and practice of modal scales for any musician. 

                In this Learning Music With Ray video I discuss the definition and composition of modal scales.  I list the seven types of modal scales, cover a brief history of the origin of modes and discuss the practical modern day applications of these scales.  I also cover tips on how to determine the pitches of any modal scale.