Gregorian Modes

These are the Gregorian Modes used during the Middle Ages. Notice the similarity between these and the major scale and natural minor scale (Key of C).



The Ionian and Aeolian Modes formed the basis of the major scales and the natural minor scales. The other modes today are used in jazz and other forms of music. The song "Norwegian Wood" uses the Mixolydian mode. Many Other songs tend to be either Ionian, Aeolian or make use of the blues scale. The latter does not adhere to any of these modes. It is a scale with African origins.

Major Scales

There are 12 major scales. Those notes that are sharp or flat make use of black keys on a keyboard. Note that Gregorian modes make use of white keys only -- and that major C is based on the Ionian mode. The minor scales are based on the Aeolian scale. The A minor scale is a relative minor key of the C major scale, whereas The C minor scale is a parallel minor scale.



Not all of these scales are used by non-transposing and transposing instruments. In some cases, even though there is a key change to one of these keys, the key signature used may not change (notably to adjacent keys on the Circle of 5ths). Some keys are enharmonic.

Minor Scales

To learn any of the major scales, one must know the whole steps and half steps that are applicable to C major and every other derived major scale. It is:

W-W-H-W-W-W-W-H

The first note is the tonic note. An A minor scale will start on A and end on A -- and have a pattern that corresponds to the minor scale used. There are three classifications: natural, harmonic and melodic. The latter descends like the natural scale (i.e. backwards).

Natural: W-H-W-W-H-W-W
Harmonic: W-H-W-W-H-aug2nd-H
Melodic: W-H-W-W-W-W-H

Because there are often conflicts with chord progressions and the melodic scale when it is descending, jazz compositions often substitute the melodic scale even for descending scales. Unwanted effect: Dissonance!

Blues Scales

Pentatonic Scales

A pentatonic scale is a musical scale or mode with five notes per octave in contrast to a heptatonic (seven note) scale such as the major scale and minor scale. Pentatonic scales are very common and are found all over the world. They are divided into those with semitones (hemitonic) and those without (anhemitonic).