Post #4240140
2026-07-23 10:37 UTC
Some additional thoughts and clarification:
I said m2 and P5 are “essentially” the only two generators because the other two are M7 (major 7th), which is just an m2 step down, and P4 (perfect 4th) which is just a P5 step down.
All the other intervals generate symmetric families of scales:
- M2/m7 give the two 6-note whole tone scales;
- m3/M6 give the three 4-note diminished scales;
- and M3/m6 give the four 3-note augmented scales.
Replies (1)
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@mdreid@mastodon.social 2026-07-23 10:37
I like to think of the two full generating intervals as the “melodic” generator (m2) and the “harmonic” generator (P5) because the former is common in melodic lines while the latter is the foundation of harmonic movement. Not sure how useful it is but I found it a neat way of looking at things. It does sort of explain why b9 and b13 sound so nice on the V7 chord in a ii-V-I since they create a extra chromatic voice movement that add to the tension and release parallel to the harmonic movement.