Add chords

Added tone chords are major triads with an extra note added. They are abbreviated "add" and there are mainly two types: add9 and add2 (there is also the much less common add11). In the add9 the ninth tone in the scale is added and for the add2 the second tone in the scale is added.

See diagrams of add chords:

C add D add E add F add G add A add B add

Theory

Some theory of this chord category are presented here.

Comparing the C Major Chord with the two main types of added chords:

C: C – E – G
Cadd9: C – E – G – D
Cadd2: C – D – E – G

As you may notice it is actually the same tone that is added to the C Major, but in different octaves.Some theory of this chord category are presented here.

Comparing the C Major Chord with the less common add11:

C: C – E – G
Cadd11: C – E – G – F

Much less common are minor add chords. A comparison between a regular C minor chord and a minor added chord would look like:

Cm: C – Eb – G
Cmadd9: C – Eb – G – D

It should also be mentioned that add4 and add6 exists and are played by the same principles as explained above. These variants are, however, very rare.