Chord symbol for "augmented 6" chord?

Hard to believe I’ve never encountered this dilemma before (maybe I have, and have just forgotten!), but I can’t recall how to indicate an augmented 6 chord (e.g., “Italian 6”) as a chord symbol – on paper, let alone in Dorico!

Any suggestions?


Thanks, Clendening Sound . . . ah, I see that this only applies to harmonic analysis/figured bass notation . . . I’m trying to find a way of indicating these particular chords within a chord chart, via chord symbols. But thank-you for responding!

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In general, wouldn’t this be considered a tritone-substituted Double Dominant?
Like instead of D7 > G7 > C, this would turn into Ab7 > G7 > C, or better Ab7#11 > G7 > C?


That was actually a valid question, YourMusic.Pro :smiley:

If building this chord on the note C, one begins with a Cm chord (CEbG), and then raises the root, chromatically, so that the chord becomes C#EbG.

This chord is most often used in first inversion – as Eb - G - C# – and since the interval between the bass note (Eb) and the top note (C#) is that of an augmented 6th, this type of chord is usually categorized as an “augmented 6” chord.

The chord is often described as being the result of contrapuntal movement (really, just chromatic voice-leading), and its goal is usually the V chord of the given key. In the key of G minor, it might occur in a context like this:

G minor: iv6 (Cm/Eb) iv#6 (the augmented 6 chord, Eb-G-C#) V (DF#D

I posted before checking Wikipedia…

It’s very similar, and, in fact, most jazz musicians – and someclassical/Romantic composers --interpreted it this way, but its use is different in a subtle way: an Ab7 is indeed a tritone substitute for D7, and its voice-leading may frequently see the Ab7’s Gb descend to the F in a G7 chord. But the original, classical usage sees that “Gb” as an F#, that strongly leads into the G in the subsequent G major triad.

This is fun. So there would be a real case for an “Italian 6”, if, say, the melody went from F# to G during those chords.
“Italian Six” is actually pretty cool name for a corresponding tune… :wink:


:grin: . . . . .

A normal 6th (major) chord would be C6, so a German Augmented 6th could be C#6, a French one, Cb5#6 and an Italian C#6(no5) with the correct superscripts etc

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Thanks, Kenneth!

Most people who write and read chord symbols care not a whit for enharmonic differences. A so-called augmented 6th is the same as a 7th to them, and that is as far as they go. Chord symbols are only shorthand for playing the desired notes. As I’ve said often before, they are not a tool for analysis. So IME the original question is moot.

Thanks, Mark, but the chart I’m working on is for my own theory students – some of whom come from a chord symbol background, but who are actively engaged in harmonic analysis.

Writing C+6 (no 5) (with the ‘plus’ raised a bit) would be less likely to be mistaken for a C#6🙃

Thank-you, laughreyg.