Augmented chord

augmented triad

Component intervals from root
augmented fifth
major third
root
Tuning
16:20:25
Forte no. / Complement
3-12 / 9-12

In music, an augmented triad is a triad, or chord, consisting of two major thirds (an augmented fifth). The term augmented triad arises from an augmented triad being considered a major chord whose top note (fifth) is raised, or augmented. It can be represented by the integer notation {0, 4, 8}.

Whereas a major triad, such as C–E–G, contains a major third (C–E) then a minor third (E–G), with the interval of the fifth (C-G) being "perfect", the augmented triad sharpens that fifth (to an augmented fifth), becoming C–E–G♯. In other words the top note is raised a half-tone.

"The augmented chord, (which appears upon three of the minor key,) is commonly found upon one, four, or five of a major key. In its resolution the fundamental may either remain stationary, descend five degrees, or ascend four degrees; the third may either ascend a minor second [I+, IV ( Play ) and I+, IV6
4 ( Play )], or remain stationary [I+, vi6
3 ( Play )]; and the fifth ascends a minor second. The inversions of the augmented chord may also be used [I+^♯6, IV ( Play ) and I+6
4, IV⁶ ( Play )]."

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Wikipedia