The Mystery of the Half Diminished Augmented Seventh Chord: Clarifying Misconceptions

Many musicians and music theorists have puzzled over the naming and classification of specific chords, leading to various debates and misunderstandings. One such chord that often confounds even experienced musicians and music scholars is the so-called "half diminished augmented seventh chord." In this article, we will delve into the intricacies of this chord, explore its correct classification, and address common misconceptions.

Common Misconceptions

The term "half diminished augmented seventh chord" is often used, but it is indeed a misnamed or incorrect terminology. It refers to a combination of different chords that may not accurately describe the structure of the chord in question. Instead, this particular chord is more accurately described as a dominant ninth in first inversion or a G9/B chord. This alternative nomenclature better reflects the chord's true structure and function.

Chord Structure of a Half Diminished Augmented Seventh Chord

The "half diminished augmented seventh chord" is often built on the seventh degree of a major scale. In the key of C major, this would be the chord of Bmin7. By adding an augmented ninth (G) to this chord, we get the structure:

B D F A G (augmented ninth)

The augmented ninth (G) is enharmonically equivalent to F double sharp. While it is tempting to use the term "half diminished augmented seventh chord," it is more precise to describe it as a G9/B chord, which accurately reflects its component notes and structure.

Revisiting Chord Terminology

Let's break down the components of this chord to understand it better:

Minor Triad

Root (1) Minor third (b3)

Diminished Triad

Root (1) Minor third (b3) Diminished fifth (b5)

Half Diminished Seventh Chord

Root (1) Minor third (b3) Diminished fifth (b5) Diminished seventh (b7)

Augmented Seventh Chord

Root (1) Major third (3) Perfect fifth (5) Augmented seventh (7)

Considering the above structures, the "half diminished augmented seventh chord" actually refers to a half diminished seventh with an added augmented ninth. The structure is:

1 b3 b5 b7 augmented ninth

However, to avoid confusion, it is more appropriate to say it is a G9/B chord, which is a dominant 9th in first inversion.

Conclusion

The "half diminished augmented seventh chord" is a complex and often misunderstood chord. By understanding its structure and correctly naming it, musicians and music theorists can avoid confusion and better appreciate its unique role within a song or piece of music. This article has provided a clearer understanding of the proper classification and nomenclature for this chord, paving the way for a more accurate and effective music theory.

For further exploration, musicians and music enthusiasts are encouraged to study chord progressions, scales, and harmony in depth to gain a deeper understanding of the myriad possibilities within musical composition.