# Secondary dominants

I saw this progression as an example on an article about secondary dominants:

```    C Am B7 C
```

Is the idea here to have B7 as the dominant of E which is the dominant of Am?

• Missing some key info. Is the key supposed to be C? Am? G? Em? Oct 23, 2019 at 4:18

Is the idea here to have B7 as the dominant of E which is the dominant of Am?

Am -> B7 -> E -> Am would be a commonly used example of a secondary dominant, yes. But having C come after the B7 seems like either a mistake or just a bad example.

The fact that the B7 isn't actually followed by an E7 doesn't make the B7 any less a secondary dominant though. During the B7 you may have expected an E chord ... but, surprise? C! Then again, you could stop the song before the C, and then we could only guess if that was supposed to be the real end of it.

(You may disagree on the previous paragraph, and there are many points of view... see this question: What Constitutes a Secondary Dominant?)

• You can analyze it as I -> vi -> V7/iii -> VI/iii, where VI/iii = I is a deceptive resolution of the dominant chord. Oct 23, 2019 at 7:51

If this is an introductory example to secondary dominants, then it is a bad one. It should be saved for later lessons.

You are correct to assume that B7 is secondary dominant to E. So, as piiperi said

``````Am B7 E Am
``````

would be a better/simpler example.

Just to expand on the topic, I'd like to point two things out:

There are secondary dominants to other degrees of the scale (not only to the dominant). So you could have

``````Am C7 F Am
``````

or even

``````Am A7 Dm Am
``````

and still remain on the tonality of A minor. Also, the example you posted could be explained as secondary dominant leading to a simple deceptive cadence: C is VI of E minor. This would also work if it led to C#m (vi of E major). Then again, if you want to stay on Am, this would lead to a more distant chord. Using this example as an introductory one is a bit too much.

• I was going to write an answer explaining it as a deceptive cadence (the final C chord being both I and VI/iii, with the B7 being V7/iii), and I almost missed that you had already said this right at the end, hence this comment to point others to this. Oct 23, 2019 at 7:44

There are no secondary dominants in that example!

Secondary dominants are chords which lead to diatonic chirds, not actually being diatonic themselves. So, if the sequence shown is in Am, that B7 should be leading to E or Em. If the sequence is in C, the same applies.

The clue is in the name. There is only one dominant of a key - that chord built on the 5th note. Thus, in key C, it's G (or G7).

A secondary dominant is the dominant of another chord from the relevant key. Here, it's C.. Were that other chord Dm, its secondary dominant is A. Were it Em, its secondary dominant is B (or the quoted B7). Were it F, the secondary dominant is C7. Were it G, it's D(7), and Am would need E(7). Each secondary dominant includes notes which are non-diatonic - called chromatics.

• Do you mean that in an Am context if you hear B7 all of a sudden, you won't be able to call it a secondary dominant until you know what actually happens after it? So, secondary dominants only exist in hindsight? And even if there's an E7 after the B7, even then you have to get an Am after it or otherwise the E7 wasn't a dominant and so the B7 wasn't a secondary dominant either? I think you should be able to listen to music, analyze and describe your feelings in real time, not only in hindsight. IMO, "leads to" is better understood as "points to". Oct 23, 2019 at 8:26
• @piiperi - interesting point. I just feel that it gets called a secondary dominat as it leads to a particular place. As in key C, if there's E7>Am it's a sec. dom., but if there's E7>F it won't be called a sec. dom., as it's not performing that particular role at that time. Will double check, though! According to Wiki, a sec.dom is usually, but not always, followed by a tonicised chord.
– Tim
Oct 23, 2019 at 9:09
• There seem to be different schools of thought. We've had some discussion about the use of the term "dominant seventh" as a description of a chord type, as opposed to "major seventh". Some people think that you shouldn't use the word "dominant" unless its tonic actually happens - which of course assumes a pre-defined progression, basically a written score of the tune. But IMO it's better to have a real-time perspective, so you describe different possible interpretations - it's all just potentials for something. That way lends itself to understanding ambiguities in harmony, in jazz etc. Oct 23, 2019 at 9:19
• @piiperi - I understand the 'real time' analysis, but analysis usually, with most things, is done retrospectively - 'so what exactly happened'. As such, if , in key C, an E chord is followed by an F, it's unexpected, so makes interesting listening, as we're sort of programmed to expect an A/Am, but whether this gives the E claim to be sec. dom. - is another question - about to be posed!
– Tim
Oct 23, 2019 at 9:45
• @piiperi I agree with Tim. Taking you “real time” POV seriously, you can't really analyse anything at all because all chords could have a whole lot of different functions. It's the context – and specifically the “what comes next” – that actually narrows it down and makes the concept of functions meaningful. Sure, some ambiguity is fine and can be desirable, but if everything is completely ambiguous then you might as well not bother classifying anything at all. Oct 23, 2019 at 13:59