The Dominant 7th Tree of Scale Choices
The two most important notes in any scale are the 3rd and 7th.
When soloing, they tell the listener what the quality is: major, minor, dominant 7th , etc.
The 3rd tells you if the quality is major or minor.
The 7th tells you whether the sound is stable or wanting to move on to another chord.
The 3rd's and 7th's are the stable tones. They are often played on beats 1 and 3.
In 4/4 time beats 1 and 3 seem to want roots, 3rd's, 5th's and 7th's. The flat 9th (b9) is also emphasized a lot over dominant 7th chord/scales.
Placing chord tones on the beat and especially beats 1 and 3 helps establish the ever changing tonality for the listener. This may be one of the most important devices in music. ALL MUSIC!
It is very important to be familiar with the chord tones: 1, 3, 5, 7, 9.
Knowing where they are on your keyboard is like knowing where the kitchen, bathroom, telephone and front door are.
Any of the scales (qualities/sounds) listed below may be played when a dominant 7th chord/scale RESOLVES to a chord/scale whose ROOT lies up a perfect fourth.
A perfect fourth equals 5 half-steps.
The Dominant 7th Tree of Scale Choices
3rd's and 7th's are bolded!
Dominant 7th = C7 = C D E F G A Bb C. This is the basic dominant 7th sound. Be careful how you treat the 4th note of the scale.
Bebop Scale = C7 = C D E F G A Bb B C. Play the B natural as a passing tone, always on the upbeat, never on the downbeat.
Lydian Dominant = C7+4 = C D E F# G A Bb C. The +4 was/is a favorite note in Jazz. It used to be called a flat 5th.
Whole Tone = C7+5 = C D E F# G# Bb C. This scale only has six tones. It is a symetrical scale used often in cartoon music and Debussy or Ravel. It also has a +4.
Diminished = C7b9 = C Db D# E F# G A Bb C. This scale has 8 different tones and is symetrical. It, too, is used a lot in cartoon music.
Diminished Whole Tone = C7+9 = C Db Eb E F# G# Ab Bb C. This scale has four altered tones and they create beautiful tension in music.
Spanish or Jewish Scale = C7(b9) = C Db E F G Ab Bb C. This scale is used often when playing in a minor key. It is the same as F harmonic minor.
Chromatic Scale = C7 = C Db D Eb E F F# G G# A Bb B C. This is the musical alphabet. ALL other scales are derived from this scale. It has 12 different tones.
With practice, you will be able to play any note at any time, against any chord/scale symbol.
This takes some time and comes as you become more and more familiar with the various sounds that make up the harmonic jazz stew.
There is really no end to what you can do harmonically.
The mind keeps thinking of new things to try!