Q about doubled thirds in chord transitions

Hello,

my name is Peter and I am currently studying Arnold Schoenberg's Theory of Harmony and I've come across a bit of confusion which hopefully you may help me out with.

At the moment I am working on chord transitions exercises using old voice leading rules that basically forbid the use of parallel fifths and octaves when using parallel motion between two voices. I understand that reasonably well however Schoenberg also mentions doubling of the third in this passage ...

"In some cases he will discover parallel octaves and fifths and must discover how to evade them. In some others it will be necessary to dispense, in part, with the sustaining of common tones because otherwise the superfluous doubling of the third would result." (page 71 in the Inversions:Connections of Chords section).

I'm pretty sure hes talking about sustaining two voices that are a interval of a third apart during a chord transition.

My question is when he mentions doubled thirds, is he only concerned about the third interval between the root and the third or would the interval between the third and the fifth also be considered since that is technically a third interval as well.

This might all sound confusing to someone who hasn't read the book and my explanation probably is not that clear in the first place but if anyone can help me out I would really appreciate it. And I can clear up any confusion that might arise.

One thing I was also curious about was this whole idea of sustaining thirds in chord transitions and wondering why it used to be considered bad practice in the first place.

Thanks for reading this and hopefully I'll hear from you soon.

When he discusses doubled thirds he means specifically the third of the triad, reason being that it's the most conspicuous constituent tone in the triad and therefore the least in need of reinforcement by doubling. (Page 36 of my paperback copy.) So it's not about thirds in general.

I don't remember anything about the sustained thirds, though, but I'm intermittently going through these sections myself so maybe I'll run into it at some point.

Edit: I see you gave a page number, and I looked it up. I think what he means is that if you run into a situation where you're sustaining a doubled tone (which isn't the third) into the next chord (in which it is the third), you should see if you can make the doubling note move instead of sustaining.

Second edit: Look on page 72, the third and fourth example of I6 - III.

Oh, that makes sense. So he's basically talking about avoiding a transition that would result in a chord with the third doubled. Thanks a bunch my friend that was really helpful and I think I'll be able to continue these exercises now!

That's exactly as I understand it as well.

The "rule" not two double the third of the triad applies of course mostly in strict 4-part harmony, but is also in some other cases important to keep in mind, particularly when the the third is already stressed by being in the bass (i.e. in a sixth chord). But even then it depends a lot on the function of the chord: It's especially problematic when the third is a leading tone (such as in the dominant), partly also because resolving doubled leading tones properly leads to parallel octaves, whereas it's even the standard thing to double the third in a neapolitan sixth chord, since this third is in that case the root of the subdominant the neapolitan is a variant of.

But in most cases it's good to assume that you can double the fundamental and "neutral" roots and fifths of a chord without problem, while you should be careful with doubling the more "colouring" and tension-creating notes such as thirds, sevenths, ninths, etc.

That would make sense that he mentioned these concerns now since the exercises I'm working on at the moment involve connecting 6th chords to regular 4 part triads.

Thanks for the feedback its helpful and interesting stuff.