This tab illustrates how to play diatonic 9ths.
we will use Ab as our example.

9ths are simply just 2nds up an octave.
(if you don't know what i'm talking about, check out my intervals tab)

example)
 
 |root    2nd     |root    9th     |
 |Ab      Bb      |Ab      Bb      |
G|————————————————|————————3———————|
D|————————————————|———————(8)——————|
A|————————————————|————————————————|
E|4———————6———————|4———————————————|
 |1 + 2 + 3 + 4 + |1 + 2 + 3 + 4 + |

notice how the 2nd and the 9th are the same note.
the note in () is another place you can play the Bb.


Now we'll chart out each 9th for each note in Ab major:
(notes in Ab major: Ab,Bb,C,Db,Eb,F,G)

I will label the quality of the 9th above the tab.

 |1) major ninth  |2) major ninth  |3) minor ninth  |4) major ninth  |    
 |Ab      Bb      |Bb      C       |C       Db      |Dd      Eb      |
G|————————3———————|————————5———————|————————6———————|————————8———————|
D|———————(8)——————|———————(10)—————|———————(11)—————|———————(13)—————|
A|————————————————|————————————————|————————————————|————————————————|
E|4———————————————|6———————————————|8———————————————|9———————————————|
 |1 + 2 + 3 + 4 + |1 + 2 + 3 + 4 + |1 + 2 + 3 + 4 + |1 + 2 + 3 + 4 + |

 |5) major ninth  |6) major ninth  |7) minor ninth  |    
 |Eb      F       |F       G       |G       Ab      |
G|————————10——————|————————12——————|————————13——————||
D|———————(15)—————|———————(17)—————|———————(18)—————||
A|————————————————|————————————————|————————————————||
E|11——————————————|13——————————————|15——————————————||
 |1 + 2 + 3 + 4 + |1 + 2 + 3 + 4 + |1 + 2 + 3 + 4 + |

You can also play them as chords:

 |Ab (9)  Bb (9)  |C (b9)  Db (9)  |Eb (9)  F (9)   |G (b9)  Ab (9)  |
G|3———————5———————|6———————8———————|10——————12——————|13——————15——————|
D(8)—————(10)—————(11)————(13)—————(15)————(17)—————(18)————(20)—————|
A|————————————————|————————————————|————————————————|————————————————|
E|4———————6———————|8———————9———————|11——————13——————|15——————16——————|
 |1 + 2 + 3 + 4 + |1 + 2 + 3 + 4 + |1 + 2 + 3 + 4 + |1 + 2 + 3 + 4 + |


All of the notes in () are just another place where you can play that note.
Ninths are great to use because they have a very open sound.
They do not establish if a chord is major or minor.
This means that you can use them on many different types of chords.
 
That being said, i'm talking about the ninths (9), not the flat ninths (b9)
Ninths (or major ninths) sound good as chords and/or arpeggios.
flat ninths (or minor ninths) are incredibly dissonant.
in my opinion, they sound horrible as chords.
they can work well as arpeggios to create riffs.
other than that, flat ninths are very inpracticle.

Ninths work very well when adding the 5th and the 3rd(10th) with it.
here's the guitar part to "every breath you take":

 |G major (9)     |                |E minor (9)     |                |
 |G D A D B A D A |G D A D B A D A |E B F#B G F#B F#|E B F#B G F#B F#|
 |1 5 9 5 3 9 5 9 |1 5 9 5 3 9 5 9 |1 5 9 5b3 9 5 9 |1 5 9 5b3 9 5 9 |
G|————————16——————|————————16——————|————————12——————|————————12——————|
D|————19————19——19|————19————19——19|————16————16——16|————16————16——16|
A|——17——17————17——|——17——17————17——|——14——14————14——|——14——14————14——|
E|15——————————————|15——————————————|12——————————————|12——————————————|
 |1 + 2 + 3 + 4 + |1 + 2 + 3 + 4 + |1 + 2 + 3 + 4 + |1 + 2 + 3 + 4 + |

 |C major (9)     |D major (9)     |E minor (9)     |                |
 |C G D G E D G D |D A E A F#E A E |E B F#B G F#B F#|E B F#B G F#B F#|
 |1 5 9 5 3 9 5 9 |1 5 9 5 3 9 5 9 |1 5 9 5b3 9 5 9 |1 5 9 5b3 9 5 9 |
G|————————9———————|————————11——————|————————12——————|————————12——————|
D|————12————12——12|————14————14——14|————16————16——16|————16————16——16|
A|——10——10————10——|——12——12————12——|——14——14————14——|——14——14————14——|
E|8———————————————|10——————————————|12——————————————|12——————————————|
 |1 + 2 + 3 + 4 + |1 + 2 + 3 + 4 + |1 + 2 + 3 + 4 + |1 + 2 + 3 + 4 + |

They also sound good as chords with the 5th in it like this:

G|11——————————————|11——————————————|
D|9———————————————|————————————————|
A|7———————————————|14——————————————|
E|————————————————|12——————————————|
 |1 + 2 + 3 + 4 + |1 + 2 + 3 + 4 + |

(These chords are both E5(add9) they're just different ways to play them)

These are just two of the many great uses for ninths.
explore the possibilities!

message me for any questions,
and please give me constructive criticism.

—Connor Larkin