Intervals in Music Theory  are essential for understanding how different notes relate to each other, creating harmony and melody.



WHAT IS AN INTERVAL?

 

An interval is the distance between two note. Include both notes when you count).


The INTERVALS SQUARE is used to help determine the type of internal. There are five types,: Perfect, Major, Minor, Augmented, and Diminished.

Each step between each category on the INTERVALS SQUARE represent SEMITONE steps. e.g. MAJOR to AUMENTED is one SEMITONE higher.

It's important to use the INTERVALS SQUARE in conjunction with knowledge of KEYS AND SCALES for both Major keys and relational Minor keys.

INTERVAL RULES


To identify a musical interval correctly the following procedure can be followed.

An interval consists of two notes, a lower note and a higher note.


Step 1
For an Interval that is less than an octave (8 notes) count the interval. Include both notes.

Intervals that are more than an octave are called COMPOUND intervals. Pencil in a new note an octave higher than the lower note. Then follow the counting procedure above.

Step 2
Identify the key of the lower note. If you don't like the lower note, then INVERT the Interval first. See INVERTED INTERVALS below.

Step 3
Write out the scale of the lower note. Compare the counted interval with the written out scale.

Consult the INTERVALS SQUARE.

Start with either PERFECT for 4ths, 5ths and 8ves or MAJOR for 2nds, 3rds, 6ths and 7ths.

Compare the higher note on the interval to the written out scale.

PERFECT INTERVALS


Higher than PERFECT is AUGMENTED (make bigger). Lower than PERFECT is DIMINISHED (make smaller).


MAJOR INTERVALS


Higher than MAJOR is AUGMENTED (make bigger).

Lower than MAJOR is MINOR ( I e one semitone lower)

Even lower than MINOR is DIMINISHED (make smaller).

INVERTED INTERVALS


Working with intervals the key of lower note needs to be established. If you don't like the lower note INVERT.

Take the upper note and write it an octave lower on the stave (below the lower note). Follow the Interval identifying procedure above. You now have two intervals. Remember it is the first interval you are interested in.

When inverting INTERVALS the following relationships apply.

PERFECTS stay PERFECT

MAJORS become MINORS and vica versa

AUGMENTEDs become DIMINISHED and vica versa.