© 2001
KEY ENVELOPE. Closely related musical keys and chords. First. major scale relationships will be narrowed as to which are closest, or easier to move into when playing.Problems arise when the musician wants to return to the original key. What to do and how to get there without being abrupt. Sort of sneak into the key.
To do this we need to understand the tetra chord pattern.
Each tetra chord consists of four tones with the following spacing between tones. Whole step + whole step + half step. Each tetra chord is linked to the other tetra chord by a whole step.
The symbol ^ indicates a half step. Two ^^ indicate a whole step. In the C major scale we have the following notes C^^D^^E^F^^G^^A^^B^C.
The first four tones C^^D^^E^F form the first tetra chord. The second four tones G^^A^^B^C form the second tetra chord. The tetra chords are linked by a whole step, or marked L1.
Now in looking at the scale we have the tetra chords defined and how they are linked together. C^^D^^E^F L1 G^^A^^B^C
For more detail on tetra chords look at lessons #1596, #1601, #1608 All same title - Part One, Part Two, Part Three, respectively. If we look at diagrams we have two distinct parts.
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| Two Tetra Chords with link |
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