Minor/Diminished/Augmented Intervals

Treble Clef

In addition to major and perfect intervals; minor, augmented, and diminished intervals also exist. A diminished interval has one less half step than a perfect interval.

C to Gb would be a diminished fifth (6 half steps).

Since C to G is a perfect fifth (7 half steps), C to Gb would be a diminished fifth (6 half steps).

B to F is also a diminished fifth

B to F is also a diminished fifth (since B to F# is a perfect fifth).

C to F# would be an augmented fourth (6 half steps)

An augmented interval has one more half step than a perfect interval. Since C to F is a perfect fourth (5 half steps), C to F# would be an augmented fourth (6 half steps).

F to B is also an augmented fourth

F to B is also an augmented fourth (since F to Bb is a perfect fourth).

C to A# is an augmented sixth (10 half steps).

Major intervals can be augmented by adding a half step. For example, since C to A is a major sixth (9 half steps), C to A# is an augmented sixth (10 half steps).

Db to B is also an augmented 6th (Since Db to Bb is a major sixth).

Db to B is also an augmented 6th (Since Db to Bb is a major sixth).

C to Bb is a minor seventh (10 half steps)

Subtracting a half step from a major interval does not make it diminished; instead, it becomes minor. For example, since C to B is a major seventh (11 half steps), C to Bb is a minor seventh (10 half steps).

C to Bbb would be our diminished seventh (9 half steps).

Only after subtracting another half step does it become diminished. Thus, C to Bbb would be our diminished seventh (9 half steps).

Number of half-steps	Minor, major, or perfect intervals	Short	Augmented or diminished intervals	Short	Widely used alternative names
0	Perfect unison	P1	Diminished second	d2
1	Minor second	m2	Augmented unison	A1	Half step
2	Major second	M2	Diminished third	d3	Whole step
3	Minor third	m3	Augmented second	A2
4	Major third	M3	Diminished fourth	d4
5	Perfect fourth	P4	Augmented third	A3
6			Diminished fifth	d5	Tritone
6			Augmented fourth	A4	Tritone
7	Perfect fifth	P5	Diminished sixth	d6
8	Minor sixth	m6	Augmented fifth	A5
9	Major sixth	M6	Diminished seventh	d7
10	Minor seventh	m7	Augmented sixth	A6
11	Major seventh	M7	Diminished octave	d8
12	Perfect octave	P8	Augmented seventh	A7

In music, the terms consonance and dissonance form a dichotomy in which these terms make a distinction between levels of sweetness / harshness, pleasantness / unpleasantness, acceptability / unacceptability, of sounds or intervals.

Therefore notes that sound good or agreeable together when played at the same time are called consonant. Chords built only of consonances sound pleasant and "stable"; you can listen to one for a long time without feeling that the music needs to change to a different chord.

Notes that are dissonant can sound harsh or unpleasant when played at the same time. Or they may simply feel "unstable"; if you hear a chord with a dissonance in it, you may feel that the music is pulling you towards the chord that resolves the dissonance. Obviously, what seems pleasant or unpleasant is partly a matter of opinion.

Consonant Interval

Consonant Intervals:
Minor Third, Major Third, Perfect Fourth, Perfect Fifth, Minor Sixth, Major Sixth, Octave.

Dissonant Intervals

Dissonant
Minor Second, Major Second, Tritone, Minor Seventh, Major Seventh

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