Understanding Intervals - Part 4



Now if you know more than the basic major and minor chords you’re going to start asking questions like: Hey what about the 9th chord or the 11th chord? What are the intervals in those? Well a ninth is simply a 2nd + 1 octave. Actually going back to that ‘Jimi Hendrix’ chord, it’s probably more accurate to call that augmented 2nd an augmented 9th, since it’s already up an octave.

The intervals you’ll hear about above the octave are the 9th, 11th and 13th. The reason why you don’t hear much about the 10th, 12th or 14th is that they really are just a 3rd, a 5th and a 7th. 3rds, 5th and 7ths sound good straight above the root note, where as 2nds, 4ths and 6ths tend to sound better up an extra octave. Calling a 2nd a 9th specifies that it must be at least 1 octave above the 2nd. Same goes for 11ths and 13ths.

Finally here’s a complete table with all the possible names for intervals:

Fret	Interval name(s)
0 (open string)	Root, Dimished 2nd, Dimished 9th
1	Minor 2nd, Minor 9th
2	Major 2nd, Major 9th, Diminished 3rd, Diminished 10th
3	Minor 3rd, Minor 10th, Augmented 2nd, Augmented 9th
4	Major 3rd, Major 10th, Diminished 4th, Diminished 11th
5	Perfect 4th, Perfect 11th, Augmented 3rd, Augmented 10th
6	Aumented 4th, Augmented 11th, Dimished 5th, Dimished 12th
7	Perfect 5th, Perfect 12th, Diminished 6th, Diminished 13th
8	Minor 6th, Minor 13th, Augmented 5th, Augmented 12th
9	Major 6th, Major 13th, Diminished 7th, Diminished 14th
10	Minor 7th, Minor 14th, Augmented 6th, Augmented 13th, Dominant 7th*
11	Major 7th, Major 14th
12	Octave, Augmented 7th, Augmented 14th

* The minor 7th is also refered to as the 'Dominant 7th'.