Applying Bebop Principals to Diatonic Scales
Jack Laskey
As a beginning improviser, one may at first feel constrained to diatonic
notes when improvising over chord changes. For example, when one sees a G7
chord they may feel as though their only note choices are those in the G
mixolydian scale. However, it is important to recognize that one always has
access to all twelve notes as opposed to the seven diatonic notes as long as they
phrase them in a musical way.
While at first tackling all twelve notes may appear nauseating, one way to
incorporate them into one’s playing is by rewriting a diatonic scale using every
note. One can do this by utilizing two bebop principals, enclosure (either diatonic
or chromatic) and chromatic passing tones.
Enclosure is when a target note is preceded by the two notes adjacent on
both sides. A diatonic enclosure is when those two preceding notes are the two
adjacent notes in the diatonic scale. For example, in the tonality of G mixolydian
one could diatonically enclose the 4th degree, C, with the note before in the
scale, B, and the note after D. This could be either D then B then C or B then D
then C. Below are both treble clef examples of this diatonic enclosure.
In both examples, the 4th degree of the G mixolydian scale has been enclosed
diatonically.
A chromatic enclosure occurs when a target note is preceded by the two
adjacent notes chromatically. Targeting the same 4th degree of G mixolydian, C,
those notes would be B and Db. Below are two treble clef examples of this
chromatic enclosure.
A chromatic passing tone occurs when a half step is inserted between two
diatonic notes. For example, in the G mixolydian scale, this could be an F#
between F and G. Two treble clef examples of this chromatic passing tone are
shown below.
In order to turn any diatonic scale into a twelve tone scale, one can insert
a chromatic passing tone between each whole step interval in the scale and
enclose every note preceded by a half step. These enclosures can be chromatic
or diatonic, but in the examples they will all be diatonic when the scale is
ascending and chromatic when the scale is descending. What keeps the integrity
of the scale in this chromaticized version is the fact that every down beat is a
note of the original diatonic scale.
Below are several examples of diatonic scales with these principles
applied.
1. G Mixolydian Ascending and Descending
2. F Dorian Ascending
3. C Phrygian Descending
4. Eb Lydian Dominant Ascending and Descending
How to practice these materials:
1. Apply bebop principles to all diatonic scales ascending and descending
(keep in mind ascending and descending will be different due to
enclosures). Use both diatonic and chromatic enclosures but be specific.
Know which you are using.
2. Be able to start these scales on any scale degree.
3. Practice starting on a note outside of the diatonic scale and use bebop
principles (enclosure and passing tones) to get back to either the diatonic
scale or the chromaticized diatonic scale.
4. Incorporate elements of 1-3 into improvisation through specific practice.
For example, play a chorus using only descending or ascending
chromaticized scales. Another example would be starting every line on a
non-scale note.
The Goal: Start playing more chromatically! Not all of the time (certain musical
situations will call for more diatonic playing), but be able to pull out any note at
any time and make it work. This will help in both tonal and ambiguous forms.