Hugely important scale in jazz
Jazz dominant is also called alt dominant. There are several ways to analyze this. I’m going to present the only way that makes sense to me, as a musician. Let’s form this in the key of C, You may want to look at what octatonic and whole tone scales mean.
- Start with octatonic: but only use the first four notes:
C D Eb E
- Then use the whole tone scale: C D E F# Ab Bb C. Use the last four notes:
F# Ab Bb C
- Now put them together:
C D Eb E——–F# Ab Bb C
The reason this is the best way to make this scale is that it gives you a sane spelling. A C7b5 has E and Bb, so your scale needs to also have those notes. b5 can also be #4, so the spelling of that degree varies from key to key. b6 can also be #5, but (b)7 needs to be a 7 because of the chord the alt dominant scale goes with.