Where to Begin - Secondary Dominant Chords

Hi, it's Chris with Implied Music, and today I want to talk about secondary dominance. We've been asking ourselves the question where it began, and we've looked at scales, seventh chords, dominant chords, but now we're going to talk about secondary dominance. Well, it's a pivotal idea in music theory and in the development of, you know, Western European music theory, and it shows up in jazz and kind of like all the time. What's a secondary dominant? By the end of this video, I think you'll know. Before we begin, just a little housekeeping. If this is the second or third video of mine you've seen and you're not subscribed, now's the time to subscribe. It really helps the channel a lot. We're building a community here of people who are interested in expanding their musical vocabulary, their musical knowledge, with the hopes of just making their own music better. I hope this is music theory for everyone. Yay, right? The channel recently has grown, expanded quite a bit, so we're reaching more people. Shout out to my OGs. I know a lot of you guys have been watching these forever, but listen, this where to begin series is an incredibly useful tool just for sort of getting the basic vocabulary, and one of the important vocabulary pieces is the expression secondary dominant. Well, a little review just to get started, and then we'll kind of like jump into the next level. If you already think you know exactly what a dominant chord is and you've got a good handle on your scales and how the seventh chords fit into the diatonic series and the circle of fifths, probably skip the review and just hop to the next chapter, but we'll try to keep this brief and smart. All right, let's just jump in. I just want to remind you guys that every major scale, and this is the C major scale, has triads and seventh chords built in. That's C major 7, D minor 7 on the third step of the scale, another minor 7 chord, a major 7 chord, and then here on the fifth step of the scale, the all-important dominant G7. G7 has in it two notes that make a tritone, and that tritone is the engine of western music theory. Without this tritone wanting to do this, to resolve, we wouldn't be able to have, I don't know, it's like there's so much we wouldn't be able to do or wouldn't have happened in music theory. And, you know, it's great in one key. C, G7, G7, back to C. I mean, there's tons of, like I would just say, folk tunes that just use this idea. But what if you want to go further afield? That's what a secondary dominant is for, because we've got to ask ourselves an important question. What's the dominant chord to G? Well, it turns out you can just go to the fifth step of the scale. So if I'm on G, this used to be a dominant chord, but now it's just going to be G. I'm going to go and get to D, and I get to D7. D7 is the five of G. However, D7, look at these notes, the F sharp is not in the key of C. It's an alteration, and it's an alteration that makes it a major triad with a minor seventh. It makes it a dominant chord. It turns it into a secondary dominant. D7 goes to G. E7 goes to A minor. A7 goes to D minor. D7 goes to G. G7 goes to C. A string of secondary dominants. A secondary dominant is just a dominant chord that pushes you to a place that wasn't in the original key. In classical music and in music of the Baroque, that frequently can last eight measures or so. Composers will begin a piece in one key, put a little secondary dominant twist in by inserting an alteration to a chord, which previously was minor, and now it's dominant. Then suddenly, boom, we've landed in a new key level. A whole new melody appears in that key level. Trunca, trunca, trunca. This guy here, Mozart, was a master of this, Haydn, earlier. Bach does it too, and Bach does it in tiny little increments. Let's take a look really quickly at how it appears in one of the chorales. The chorales are great for study. They're a little bit, I don't know, heady. If you don't read music, it's a pain. Listen, I've done a MIDI version of it here. I'm going to show you the notation, and then we'll listen to the MIDI version and talk about what is going on. The section of this chorale that we're going to look at, I've highlighted in blue here. There's a pickup beat right here, and then we're off. We're in the key of G, and the very first chord is a G chord to E minor. D7 resolves to G. Really nothing terribly surprising. G, E minor. My computer is analyzing it correctly. D7, G. The next thing that happens, and you can see the accidental, even if you don't read music, this thing here is a red flag that something is changing. We get A7. A7 is the five of D. A7 is the secondary dominant, and it is crazy beautiful. Right? It's so pretty. It's really hokey pretty, but pretty pretty, right? Well, as it goes on, we get right away another secondary dominant. Remember I said when sharps appear, they're like red flags. See this sharp here? Tell me what chord this is. Well, my computer knows. It says it's B7. Incorrectly spelling the D sharp is E flat. B7 is the five of three, two, one, E. B is a fifth above E, and so the next chord is shown off E, a sort of a version of E minor. See that C is hanging out there. It's about to resolve back to the D, G, D7. Over the course of these eight bars, Bach has established the initial key, used a secondary dominant to push to D, the five, the very normal secondary dominant to go to the five, and then another normal secondary dominant to go to the relative minor, E minor. There's nothing special about this. It appears in thousands and thousands of classical tunes, yet managing it this way is so elegant and beautiful. Watch it go by. By the way, I'll say that pop songs use the same approach as well. We see all the time passing chords that act as secondary dominants, diminished chords especially. It's not used quite so much anymore, but composers like Bruce Hornsby, Sara Bareilles, all the piano player composers, Elton John, use these kinds of things all the time because we grew up, we got trained in it. I mean, it just falls under our hands. Listen to this. This is what we just saw, so watch it go by. Here's the secondary dominant, A7, to D, and then right away another secondary dominant. They always sound a little bright, and then he apologizes and returns us back home again to G. Secondary dominants create new key levels, new key centers by using tritones that want to resolve to new places. Tritones always act as leading tones. They push us to a new place. Secondary dominants, or the function of secondary dominants, appear in jazz harmony and of course neo-soul chords as well because dominant chords push us, and they always have partners. Remember the two and a five of a chord progression work together? For instance, D minor 7 and G7 work together to establish the C tonality that wants to happen. I'll do it this way. G7, C7, C major 7. In jazz, you frequently will do things like go to a new place. C minor 7. F7 takes me to B flat. Let's continue this plan. B flat minor 7. E flat 7 takes me to A flat major. Let's do D minor 7 flat Let's do G7 flat 9, and let's resolve to C minor major 7. Oh, so dark, so beautiful. Two fives are kind of a world. Two fives, two minor seven, five dominant, are kind of a world where secondary dominants sort of like are at play, but secondary dominants have been around for, I'm just going to go ahead and say centuries. Bach, master of them. Mozart, using them to create long, long pieces where key levels like change and shift and then stay there for a while as new melodies appear and dissolve. If you're just writing a four chord cycle song, you kind of don't have to worry too much about secondary dominants, but understanding how dominants tonicize, push towards new locations, I think is a really important ear skill when you're listening to a piece of music. If you notice a moment of bright tension, it's kind of how I hear them, it's likely it's a secondary dominant pushing you to a new place, and that new place might sit there for a while, or it might meander off into a new direction. Secondary dominants, they're not secondary at all, really, they're crucial to our building long structures and interesting music. Well, I hope this has been useful. Like and subscribe, ding the bell, you'll be notified when I do my videos, and I'll see you next time.