C9 notes: C E G Bb D A9 notes: A C# E G B C13 notes: C E G Bb A A13 notes: A C# E G F#If they indicate the chord is a minor 9th (Cm9) or minor 13th (Am13), then you add the extra note to a minor seventh group of notes.
Cm9 notes: C Eb G Bb D Am9 notes: A C E G B Cm13 notes: C Eb G Bb A Am13 notes: A C E G F#You can build suspended ninth chords and minor-major 13ths and all sorts of other weird chords this way. And they can be written many different ways. You’ll just have to see what harmonizes best with the melody.
The two best notes to drop are the root (I) and the 5th notes.
This may seem counterintuitive at first, but those notes are the same between every chord so playing them doesn’t really distinguish between different chords. The 3rd note is critical to distinguish between a major and a minor. Likewise, the 7th note is needed to distinguish between a dominant and a major seventh. And the extra notes such as the “sus” or “13th” are required or else, why bother?
If you’re playing with other people, you can forget about doing the root note. Someone else will be playing it. The 5th note is implied by the root so you can forget about that if you want to, also. Conversely, you can play just the basic major or minor chord if someone else can cover the extensions for you. It’s almost like a symphony where no one plays a chord. Each instrument can only play one note but together they can make a chord you have no hope to emulate on your puny little instrument.
If you’re playing by yourself, let your ear be your guide. Not every chord has to be complete in and of itself. The entire song has to hold together as a piece so choose the notes you can reach that make the song sound better.
The diminished chord is made from every other note of the diminished scale. Each note is 3 frets from its neighbor.
Thus you can drop a C7 down to a Cdim:
C7: C E G Bb C-: C Eb Gb AOf course, on the instrument, the easiest thing to do is raise the root instead of drop all the rest of the notes.
C7 : C E G Bb C#-: C# E G BbA good place to use diminished chords is right before you change to the next chord. Move up one fret and use the next higher diminished chord of the chromatic scale. Thus the basic chord progression:
I / / / | IV / / / | I / / / | V / / / |becomes:
I / / I#- | IV / / IV#- | I / / I#- | V / / / |Here it is in a few keys:
C / / C#- | F / / F#- | C / / C#- | G / / / | D / / D#- | G / / G#- | D / / D#- | A / / / | G / / G#- | C / / C#- | G / / G#- | D / / / |A good turnaround at the end of a verse or chorus also uses the diminished chord:
I I#dim VIm V7Here it is in a few keys:
C C#dim Am G7 D D#dim Bm A7 G G#dim Em D7
|D||E||Gb||Ab||Bb||C||D||(same as the C whole tone scale)|
|Scale one chords:||C E Ab|
|D Gb Bb|
|Scale two chords:||Db F A|
|Eb G B|