augmented triads

What function does an augmented triad as in E, Ab, C, have? Where does it or can it resolve? What does it follow? Can it be used for modulation (and i don't mean augmented sixth).

I believe you mean E, G# and B#...one should be careful with the enharmonic spellings...

An augmented triad naturally occurs on the third degree of harmonic and ascending melodic minor. Just as the diminished chord is ambigous and versatile when it comes to modulation because of its symmetry (no clear root), so the augmented triad. If you want to label it with one of the three functions, it may manifest dominant function (consider in minor: you have an unstable sonority, a leading tone and fifth degree).

Just as the diminished triad, it can also work as a passing chord, for example: I - I+ - IV

Here is an example of enharmonic modulation using augmented triad:

http://www.urizone.net/Words/Pics/Music/Enharmonic/EM-Aug.gif

I personally haven't used it much.

It's a symmetrical chord and doesn't have a "real" function in Common Practice music. Augmented triads didn't really come around till Debussy when he started implementing the whole-tone scale in his works, and tertian harmonies based on the whole tone scale aaaaaare augmented triads. So there you go. You can find them in earlier music (18th and 19th century) but normally that's through some kind of passing motion or non-harmonic chord tones (suspensions usually I gather).

You know, you aren't being bound by "rules". You can write whatever you want, no one's going to bite your hand if you write a E-G#-B# and move to an Eb-G-Db. Of course, I just used good voice leading, if you don't use good voice leading then yes your hand should be bitten B-)

I believe you mean E, G# and B#...one should be careful with the enharmonic spellings...

E, Ab, C is just as much an augmented triad as E, G#, B#. It's just not the root position ;)

Anyways. There are many uses of the augmented triad, the most common as a dominant (as Kamen mentioned) with a raised fifth to create an additional leading tone to the third of the tonic (in major). In harmonic minor it appears naturally on the third degree (also as a dominant). There are of course also other uses, such as a bII or bVI in major, or a bIV or bVII in minor.

I disagree with gms5287 that it's not common before Debussy. I've analysed many songs by Schumann and Brahms that made use of them. Possibly Schubert too, although I don't have an example in mind.

You know' date=' you aren't being bound by "rules". You can write whatever you want, no one's going to bite your hand if you write a E-G#-B# and move to an Eb-G-Db. Of course, I just used good voice leading, if you don't use good voice leading then yes your hand should be bitten B-)[/quote']

It actually doesn't seem like great voice leading if you write it enharmonically exactly like that :P None of the three notes of the augmented triad resolves naturally like that! Either write the augmented triad as Fb, Ab, C, or the resolution as D#, Fx, C#. Tsk!

Hey. Sorry to argue with what's been said but the above is completely untrue.

Augmented triads are actually fairly common place in common practice harmony.

I can think of hundreds of examples including most minor key Bach chorales, a lot of Mozart's works and they are extremely common in all Romantic works, but in particular Schubert (an extreme case is Der Atlas from Schwanengesang, which is full of them) and Schumann come to mind. Another composer who used them all the time was Purcell. (Check out the end of Remember not Lord our Offences)

They are actually not usually passing harmonies at all. They have a function. That function is almost always that of a substitute dominant. In simple terms they replace chord V at cadences and are often used to add expressive dissonance to the cadential material.

These cadences are not usually considered to be 'structural cadences', however.

Because they are ambiguous, i.e. there are only four augmented triads in total and they all have a few possible resolutions, they are often used as modulatory pivots. They also very easily approached. For example, a common Schubertian means of modulation from i to VI is via the augmented triad:

In D:

Take a D major triad in first inversion, then raise the A natural to A#. The triad is now augmented. With this spelling, (F# A# and D natural) it is of course IIIb in B minor, and with the F# in the bass, it is easy to have a quasi- perfect cadence onto i in B minor.

The reason this sounds so effective is that the chord contains both the dominant note (in this instance F#), AND the leading note (here A#). The only difference in any minor key between IIIb and V, is that IIIb has the sixth in built rather than the fifth.

In Der Atlas Schubert uses it as a pivot chord to get from G minor to B minor. This works because III in G minor contains the same pitches (enharmonically) as III in B minor.

Check it out, find out how it works and use it as the music demands!

E, Ab, C is just as much an augmented triad as E, G#, B#. It's just not the root position ;)

Depends on the key. In C# minor, it's E, G#, B#. In F minor it's Ab, C, E (natural :whistling: ).

It can be a lot of things, and can (theoretically) appear in almost any key as E, Ab, C! Harmonies don't have to consist of diatonic notes only.

Agreed, but if you write E, Ab (instead of G#), C in A minor, you risk a frown at best. Remember, it's not about having diatonic notes, it's about being easy to read for the player.

Agreed. E, Ab, C in A minor would be a very special thing.

(Of course, in a passing modulation to C major, which would be quite common in A minor, even this chord could appear.)

I agree with what matt.kaner has said. I think he hit it spot one when it comes to common practice.

Later on during Impressionism (someone earlier had mentioned Debussy) and Post-Romanticism the chord was sometimes used by itself, to display the augmented chord's distinct quality. If you can recall The Sorcerer's Apprentice, for example, Dukas uses parallel augmented chords descending by a minor third to create a dream-like quality. So you are not by any means restricted to the rules of common practice.

I was rightfully called out in this thread, sorry for my half-informed post. Though I was still right, I just didn't give the whole picture. Sorry.

Well, it's normal to complement each other. It's not unusual to miss / forget something. :)