The Interchangeability of Modes

November 19, 2010

Although the diatonic modes differ from one another, when they share a common fundamental tone (C Dorian, C Phrygian, C Lydian, etc.) that tone acts as a powerful unifying force. It may even be said that when the modes share a common fundamental tone, that tone places the modes in the same tonality (feeling of key), even though that tonality may be somewhat weaker than that of major and minor scales. Therefore, modes having the same fundamental tone may be used interchangeably in the same composition or jazz improvisation. Many examples of the technique of mode interchange may be heard in classical music. A particularly vivid example follows, from Borodin’s “Polovetzian Dances:”

Example 1

Instructions for Mode Interchange Exercises

The student should strive to perform the Mode Interchange Exercises that follow, without referring to printed music. Initially, the musical thinking should revolve around determining the transposition interval, as shown below. (The transposition interval is defined as the interval distance from the fundamental tone of the mode to the tonic whose key signature is being employed in the mode.) Ultimately, however, the student should be able to hear any given mode, starting on any pitch, without having to calculate transposition intervals.

Thinking Process for Mode Interchange Exercises

1. The Ionian Mode uses the tones of the major scale whose tonic (C) is a unison with the fundamental tone of the mode (C).
2. The Dorian Mode uses the scale tones of the major scale whose tonic (Bb) is a major 2nd below the fundamental tone of the mode (C).
3. The Phrygian Mode uses the scale tones of the major scale whose tonic (Ab) is a major 3rd below the fundamental tone of the mode (C).
4. The Lydian Mode uses the scale tones of the major scale whose tonic (G) is a perfect 4th below the fundamental tone of the mode (C).
5. The Mixolydian Mode uses the scale tones of the major scale whose tonic (F) is a perfect 5th below the fundamental tone of the mode (C).
6. The Aeolian Mode uses the scale tones of the major scale whose tonic (Eb) is a major 6th below the fundamental tone of the mode (C).
7. The Locrian Mode uses the scale tones of the major scale whose tonic (Db) is a major 7th below the fundamental tone of the mode (C).

Example 2

Mode Interchange Exercises

To achieve fluency in mode interchange, practice playing the seven diatonic modes in succession (Ionian, Dorian, Phrygian, Lydian, Mixolydian, Aeolian, Locrian) on each tone of the chromatic scale one octave apart in both hands.

The following two pages feature a Lee Evans solo-piano jazz arrangement of the American folk song Every Night, which is in the mixolydian mode.

Example 3

Example 4

Lee Evans, Ed.D., is professor of music at NYC’s Pace University. The above article is based on his Hal Leonard publication Modes Their Use In Jazz. His most recent books, published by The FJH Music Company, are the late elementary solo-piano volumes Color Me Jazz, Books 1 2; and the intermediate/late intermediate solo-piano volume Ole! Original Latin American Dance Music. Musical excerpts are from the Hal Leonard Publication, Modes Their Use In Jazz – HL00009043.

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