Basic Music Theory: How to Read, Write, and Understand Written Music

23: Intervals

Example 23.5 Altered Major intervals in the key of C.

And just to mess with your mind a little, a minor interval lowered a half

step becomes a diminished interval.

Finding an Interval

In a few easy steps you can find an interval. It’s easiest with the key of C

so we’ll stick with that for now, but you should be able to find an interval

from any note to any other note.

1 Count the lines and spaces up from the lower of the two notes. Be sure

to count the lowest note as 1.

2 Determine if the number of the interval is Major or Perfect. (M = 2, 3, 6,

7; P = U, 4, 5, 8).

3 Determine if the interval is lowered or raised from what it would be in

the Major scale. Use the Major scale which starts on the lower of the

two notes.

For example, lets take a C and a Bb, with C being the lower of the two

notes. For the first step, we count the lines and spaces to get the number

of the interval.

min2 aug2 min3 aug3 min6 aug6

min7 aug7

12 3

4 5

6 7