Basic Music Theory
is below the P because a diminished interval is lower than a Perfect
interval.
Example 23.4 Altered Perfect intervals in C major.
Altering Major Intervals.
Major intervals can also be altered by raising or lowering them.
A Major interval lowered a half step becomes a minor interval.
A Major interval raised a half step becomes an augmented interval.
Here’s another little diagram. Just like before, the aug is above because
it’s higher than the Major, and the min is below because it’s a lower than
the Major:
P
dim
aug
dimU augU dim4 aug4 dim5 aug5
dim8 aug8
M
min
aug