The Diminished Scale

        Like the bebop scale that we discussed last week, the diminished scale is composed of eight pitches.  Remember, most of the music of bebop jazz era is composed in a 4/4 shuffle feel that is complemented by flowing eighth note patterns.  A 4/4 measure can contain a maximum of 8 eighth notes, so an 8 pitch scale would be the optimal tool for musical improvisation in this musical style.  The bebop scale introduced a chromatic pitch to add interest.  The diminished scale includes several chromatic pitches and adds even more variety. 

    

       The diminished scale is composed of alternating intervals of whole and half steps.  The scale can either start with a half step or a whole step (depending on the chord it is being applied to).  So, the interval pattern used to compose a diminished scale is either W-H-W-H-W-H or H-W-H-W-H-W. 

   Since the diminished scale is based on an alternating whole step / half step pattern, there are only 3 diminished scales to learn.  Tonics that are a minor third apart share the same diminished scale.  The tonics of C, Eb, Gb, and A share the same diminished scale, and they can be thought of a group 1 of the diminished scales.  The next group of tonics that share the same diminished scale are C#, E, G and Bb (group 2).  The final group (group 3) is composed of the tonics D, F, Ab and B.  Included in the video are slides in which the scales of each of these groups are written out (in both whole/half and half/whole form).  Practicing these scales in light of the three groups will aid in both understanding and memorization. 

   Due to the alternating whole and half step pattern of the diminished scale, the rules for proper pitch spelling are ambiguous.  There are three main methods commonly applied among music theorists to achieve uniform pitch spelling.  One is the fraternal neighbors method.  In this method, the eight pitches are paired in groups of two, and neighboring chromatic pairs are given different letter names.  An example of this in the C (half/whole) diminished scale would be / C Db / D# E / F# G / A Bb /.  The second method involves stacking two diminished tetrachords separated by a whole step.  This results in the same spelling as the fraternal neighbors method, and only differs in the mental grouping of the pitches (example: C (half/whole) diminished scale: / C Db D# E / F# G A Bb /).  The third is the identical neighbors method.  Just like the fraternal neighbors method, the eight pitches are paired in groups of two.  However, now the neighboring chromatic pairs are given the same letter name (example: C (half/whole) diminished scale / C C# / Eb E / Gb G / A A#/).  For the scale examples given in this lesson, I have used the fraternal neighbors method. 

   Certain harmonies lend themselves to the use of the diminished scale in musical improvisation.  In addition, certain forms of the scale (whole/half or half/whole) are more appropriate depending on the harmony being improvised over.  When improvising over major triads and dominant 7b9 chords; the half/whole diminished scale that shares the tonic of the current chord can be used.  When improvising over minor triads, minor 7^th chords and diminished 7^th chords (fully diminished 7^th); the whole/half diminished scale that shares the tonic of the current chord can be used.  The tasteful use of these scales, in combination with the other scales we have studies, helps to provide a broader musical pallet for improvisation.  This leads to the creation of more interesting and varied melodies. 

        In this Learning Music With Ray video I discuss the definition and composition of diminished scales.  I cover the whole and half step pattern that is used to create this scale, and the proper way to spell the pitches of the scale.  I also explain why there are basically only three diminished scales to learn, and how all the other keys are related to these three.  Finally I cover which chords compliment the use of the diminished scale in musical improvisation.