Neighbours of Cadd9
Every chord one voice of Cadd9 reaches by a semitone or a whole tone, on C and so for every root: the voice that steps, the notes that result, and what they spell.
Cadd9 holds C D E G. 8 chords are one semitone away and 4 chords are one whole tone away; 7 of them spell a chord type and 0 realise a transform a source names.
One semitone away
| Voice | Steps to | Notes | Spells | Named transform |
|---|---|---|---|---|
| C | B, -1 | B D E G | G6, Em7 | none named |
| C | C#, +1 | C# D E G | no chord type | none named |
| D | Db, -1 | C Db E G | no chord type | none named |
| D | D#, +1 | C D# E G | no chord type | none named |
| E | Eb, -1 | C D Eb G | Cm(add9) | none named |
| E | F, +1 | C D F G | F6sus2, G7sus4 | none named |
| G | Gb, -1 | C D E Gb | no chord type | none named |
| G | G#, +1 | C D E G# | Eaug7 | none named |
One whole tone away
| Voice | Steps to | Notes | Spells | Named transform |
|---|---|---|---|---|
| C | Bb, -2 | Bb D E G | Em7b5, Gm6 | none named |
| E | F#, +2 | C D F# G | Gmaj7sus4 | none named |
| G | F, -2 | C D E F | no chord type | none named |
| G | A, +2 | C D E A | D7sus2 | none named |
No source this site cites names a transform for this chord type, so every step here stays unnamed.