Note relationships between two keys

[feloniuspunk]

This is a little bit detailed and complicated but stick with it, you’ll be amazed at what it reveals. What it tries to explain is the really cool relationship between the notes in a major scale and the notes that are not in the same major scale.

To start off with, there are 7 different notes in a major scale right? There are also 12 different notes within one complete octave right? So in any major scale there are 5 notes that are not played. (12-7=5) The 5 notes that are not part of the major scale are between the notes that are played.

There is a subtle but very interesting relationship that can be shown between the notes in a major scale that are played and the notes that are not played.

Let’s start with the C major scale. The notes (and chords) for the C major scale are:

C - Cmaj7
D - Dm7
E - Em7
F - Fmaj7
G - G7
A - Am7
B - Bm7b5
C - Cmaj7

The 5 notes that are unplayed (Db-Eb-Gb-Ab-Bb) form the pentatonic (Ebm) relative minor scale of Gb major (or F# major if you choose to call the notes C#-D#-F#-G#-A#). But let’s stick with calling them (Db-Eb-Gb-Ab-Bb) for now if you don’t mind.

Likewise, the notes (and chords) for a Gb major scale are:

Gb - Gbmaj7
Ab - Abm7
Bb - Bbm7
B - Bmaj7
Db - Db7
Eb - Ebm7
F - Fm7b5
Gb - Gbmaj7

The 5 unplayed notes in the Gb major scale are (G-A-C-D-E) and make up the pentatonic (Am) relative minor scale of C major!

That is the relationship that is so interesting. So, the rule is: The 5 unplayed notes in a major scale form a pentatonic relative minor scale for another key whose relationship to the original key is b5 (or #4).

Now, starting with C, list all the notes and chords sequentially for an entire octave:

1. C - Cmaj7
2. Db - Db7
3. D - Dm7
4. Eb - Ebm7
5. E - Em7
6. F - (Fm7b5/Fmaj7)
7. Gb - Gbmaj7
8. G - G7
9. Ab - Abm7
10. A - Am7
11. Bb – Bbm7
12. B - (Bm7b5/Bmaj7)
13. C - Cmaj7

Notice that the subsequent progression fits together rather nicely and makes for some very nice transitions from one chord to the next traveling either up or down.

The only two notes common to both keys are F and B, which are also separated by the same interval (#4/b5) as C and Gb. That F is Lydian in the key of C and Locrian in the key of Gb, and that B is Lydian in the key of Gb and Locrian in the key of C also points to another interesting and useful relationship.

The 5th note/chord from each scale (G7/Db7) if played as its alt. version, that is G7#9 and Db7#9, becomes what is called a "Neopolitan" 5th for the other key.

So above is another useful way to think of and use every note when writing songs, soloing, changing keys, moving from one chord to another, etc.

www.nickkepics.com

[raptor5618]

Uh ok I was thinking this very thing last night. Seriously I only wish I had the mental faculties to sit down with this and understand it enough so that I could say yes I understand what is so interesting about your post. Unfortuantely I can only understand what you are saying but need much more time to make it fit into some grand scheme. Oh how I wish I had your brain.

[Greg Jones]

Very cool stuff man!


Technically though, the B in the Gb major scale should be referred to as Cb. No? Letter names are not supposed to repeat in major scales. So 'tonically' speaking you do have the common notes F and Cb(Cb=B). Very interesting way of looking at this. I always like and appreciate new ways of thinking about these things.

Thanks for the GREAT post!

[feloniuspunk]

Good catch on the B=Cb detail.

[Marty Gilman]

A technique was first used by the composers during the Baroque Period (1600-1750) and was called pivot chord modulation, using a common chord between two keys to switch to that other key.


-Marty (profesor de musica Y espanol)