Dr. Barry Harris was one of jazz’s greatest luminaries. As a teacher, he dedicated his life to educating students all over the world about jazz and bebop language.
One of the concepts he mentioned often (aside from the 6th diminished scale) was his half-step rules, which we are going to discuss in this blog post. There are also rules for major scales and minor scales, but today, we will discuss the rules for the dominant 7 (mixolydian) scale.
Lets begin!
What Is The Dominant Scale?
Before we get into the half-step rules, let’s do some housekeeping.
The dominant 7 scale can either be explained as a major scale with a flattened 7th or as the 5th major mode (Mixolydian).
Dominant chords come from dominant scales, so this scale is most typically used over dominant chords when improvising. Barry Harris’ half step rules serves as “rhythmic placeholders” so that chord tones will land on strong beats (1-2-3-4), which is an important element of bebop.
Half-Step Rules For Scales Starting on 1-3-5-b7
1-3-5-7 Rule
One Half Step: When descending from the tonic (1), 3rd, 5th and b7 of the dominant 7 scale, you can place one half-step between the tonic and the 7th:
Example in the key of F:
3-5-b7 Rule
Three Half Steps: When descending from the 3rd, 5th, or 7th of the dominant 7 scale, you can place 3 half steps between 3rd and 2nd, 2nd and tonic, tonic and 7th.
Half-Step Rules For Scales Starting on 2-4-6
No Half Steps: When descending from the 2nd, 4th, or 6th of the dominant 7 scale, you do not have to use any half steps. (If you start odd, you end even.)
Two Half Steps: When descending from the 2nd 4th or 6th of the dominant 7 scale, you can put two half-steps between the 2nd and tonic and tonic and 7th.
Extra Rules
The Half Step Can Be Any Note?!
This may sound confusing but it is true. Remember what we said earlier? The half-step rules serve as rhythmic placeholders. The half step between tonic and 7th in the key of C doesn’t have to be B. You could use E as your “half-step” and run back down the scale. Just make sure to follow the rule for the note you play after your half-step note.
For example:
When I ran up to the third, the next note was D, which is the 2nd, so I followed the no half steps rule. I could’ve also used the 2 half steps rule, which would’ve looked like this:
Eighth Note Triplet Rule
When playing eighth note triplets, you follow the rule for the second note of the triplet. In the example below, the second note of the triplet is A, which is the 6th, so I can use either rule for scales descending from the 6th.
16th Note Triplet Rule
For 16th note triplets, you follow the half-step rule for the first note of the triplet, which in this case is C.
The Arpeggio Rule
When teaching the half-step rules, Barry Harris also speaks about the 3 “important arpeggios”. This is the arpeggio on the 1st degree of the dominant scale, (C major) the arpeggio on the 5th degree (G minor) and the 7th degree (Bb major).
Some musicians change the concept of important arpeggios into “important 7th chords”. The 7th chords that are built on the 1st (C7), 3rd (Em7b5), 5th (Gm7), and 7th (Bbmaj7) can all be used to create interesting lines.
When you play these 4 note arpeggios, you follow the half-step rule for the note you play right after.
For example, if you play a Em7b5 arpeggio and resolve down to C, you can use the first half-step rule. (Half-step between tonic and 7th).
If you resolve up to E, you have two choices. The first half-step rule, or the 2nd rule with 3 half-steps. In this example, I’m going to use 3 half-steps.
If you resolve up a third to F, you can follow any of the 2-4-6 half-step rules.
Major Scale Rule Swap
In Barry’s half-step rules for the major scale, he places a half-step between the 5th and 6th degrees of the scale.
The interesting thing is that we can also use this rule for the dominant scale. We can use a half-step between the 5th and 6th instead of between the 7th and the tonic.
All the scale rules for 1-3-5 and 7 will still work. Just remember that you have swapped out one half step for another, because putting them both together doesn’t work.
You could also swap out the half-step between the tonic and 7th to a half-step between the second and tonic, and it would work the same. This is because the half-steps serve as rhythmic placeholders. Don’t forget that!
The half-steps serve as rhythmic placeholders.
Conclusion
This the Barry Harris half-step rules for the dominant scale is a packed concept that can take many weeks/months of practice to get under your fingers, but will definitely be worth it when you see the “hip” lines you will be able to create.
If you want to your improvisation to be more coherent, the half-step rules is an excellent place to start. If you would like some more information about them, I suggest you check out Issac Raz, Things I Learned From Barry Harris, and Bill Graham Music on Youtube. These three have the most comprehensive videos on this topic.
To download a free pdf of the dominant 7 rules, click the button below.
