In this video we'll talk about triads in the context of major keys. We'll also include a short discussion of the dominant seventh chord in major keys. We'll see how those things relate to Roman numerals and figured bass and how to use all of these things to do a simple and quick harmonic analysis. Triads are special kinds of chords that have two superimposed thirds.
If you play a major scale, say in this case C major, the major scale that does not contain any accidentals, and using the notes from that scale you build triads on each of those seven scale degrees, what you have is this. Notice that I'm using here only the white keys of the keyboard, right? Only notes without any accidentals because those are the notes that pertain to the key of C major, which key signature is none, no accidentals, right? In major keys, then, we are building these triads on each of these scale degrees, and we can also, it is very customary to build a seventh chord.
on the dominant, on scale degree five. So that scale degree five can replace the dominant triad. Both are used.
We do not usually see, at least in traditional music theory and in much of the classical repertoire, seventh chords being built on any of the other scale degrees because in those cases, the seventh of each of these triads would be considered a non-harmonic tone, would have to be approached as such and resolved as such. So for example, here we have the C major triad, C, E, G. If I would add a B, a seventh on top of that, that by itself in traditional music theory, in western classical music, would be dissonant. And that B would have to be resolved somewhere, for example, by going a step up.
So really the only seventh chord that is entirely consonant in major keys is the one built on the dominant, right? The dominant seventh chord. Sometimes I've included here that it could also be built, a seventh chord here, on the leading tone that would create a half-diminished seventh chord. And that's more uncommon, I'd say.
very common to have seventh chords built on the leading tone in minor keys, but for major keys not as traditional or as common. So for the sake of sticking it to what is safe or what is traditional, I'm indicating here that we can only really build a fully consonant seventh chord on the dominant. So from those triads that we just built on C major, we can arrive at the qualities that triads will have in any major key. G major, A flat major, D flat major, E major, whatever key, major key you can think of, the qualities of the triads built on the 7th scale degrees will always be the same.
The tonic triad will always be major. The supertonic, the mediant, the submedian triads will always be minor. the leading tone triad will always be diminished. The subdominant major and the dominant major, or if you use the seventh chord built on the dominant, it'll always be a dominant seventh chord. This is very much like our previous discussion of intervals between scale degrees, right?
Once we know what the quality of the triad is for one key, it'll always be the same for that particular scale degree. any keys, right? So if this is a little bit troublesome for you perhaps to memorize, just think of C major or whatever major key comes to your mind most easily.
Put the seven scale degrees one next to each other, build triads on top of each, and assess their qualities. And you'll find out that they will always be the same. Major on scale degrees one, four, and five.
Minor on scale degrees two three and six a diminished on the leading tone scale degree seven and if you want to build a seventh chord on the dominant it'll be a dominant seventh chord. So in music we have come up with this convention of indicating the quality of triads, of chords built on scale degrees for the purpose of analyzing the harmony, how these chords succeed each other in real music. What we do is first at the beginning we indicate the key of the excerpt with a letter. If it is an uppercase letter then it's a major key.
You can see here that my key signature includes one flat B flat and that gives us two possibilities right two relative keys either F major or D minor and I'm indicating here that it is a major key the uppercase F is an F major. Then we use Roman numerals right we use 1, 2, 3, 4, 5, 6, 7 But instead of using the Arabic numbers like we have here, we use Roman numerals for that. And here we use quote-unquote uppercase numerals, not that such a thing exists, uppercase and lowercase numerals, but they do in music theory.
And when a Roman numeral is an uppercase, it indicates that that chord is a major chord, right? In this case, major triads. So here you have 1, 4, and 5 having uppercase. Roman numerals. When you have lowercase Roman numerals, that is an indication of minor triads.
Here you have two, three, and six. If you want to indicate diminished triads, of which we have only one here on the leading tone, then that is indicated with a lowercase and the superscript O. So very similar to minor, because in essence it is a minor triad with a diminished fifth instead of a perfect fifth.
You indicate it with that superscript O over there. And a dominant seventh, just as we've seen before with figured bass, it is an uppercase V and a superscript VII next to it. This is how you indicate it. Alright, so here we have the chords in F major.
I've changed the clef as well. The scale degrees by themselves would have sounded like this. And then back to I. And once we build triads on top of those and the dominant seventh chord on top of the scale degree five we have And then the dominant seventh and then six and leading to Finally back to one You can see that I've changed the key but the qualities have remained the same from what we had previously in C major.
And it holds true for any other major key. And we can put Roman numerals and figured bass together to indicate not only what chord we're looking at in the context of that specific key, but also if it is inverted or not. So here we have three examples or three excerpts in G major.
You know that because of the key signature and because of the uppercase G colon and then whatever follows it. In the first, I have a G major chord. G, B, D, right? A G major triad. G to B being a major third, B to D a minor third.
That is the recipe for a major triad. Well, G major triad in G major is built then on scale degree one. So this is a one chord or a tonic.
chord. So you have that. The next two chords, the next two triads, are the same as the first, but I'm inverting them. Here I have the third, B, being the bass, the lowest note, and here I have D, the fifth, being the bass, the lowest note. So this one is the tonic chord in G major, right, the chord built on scale degree one, but in first inversion.
We indicate that with a superscript 6, or as you've seen before, a 6 over 3. And here we have it in second inversion, because the 5th is at the bottom, and we indicate that with a 6 over 4, right? So we use the Roman numeral, and if the chord is in root position, you need nothing else. If the chord is not in root position, if it is inverted, you add whatever figured bass numbers you need.
Here is... A triad whose root is E E to G is a minor third, G to B is a major third. So this is the recipe for a minor triad.
So this is E minor. We know that this is in G major because of the uppercase letter here, because of the key signature. Given those considerations, E is scale degree 6 in G major, right?
And it follows that the triad built on scale degree 6, on the submediant. is a minor triad. So we indicate that with lowercase 6, Roman numeral 6 here. Likewise, I've inverted the chords. So the third is at the bottom here and the fifth is at the bottom here.
And so we have first inversion of the submediant and the second inversion of the submediant. And so I use the appropriate figured bass to indicate that. Good position, first inversion, second inversion, just like that. And finally here is an example of a dominant seventh chord in G major.
Scale degree 5 is if you count G, A, B, C, D. D therefore is our dominant. We build a seventh chord on the dominant. What we have is a major third D to F sharp, mind the key signature. F sharp to a minor third and then between D and C we have a minor seventh. In other words we have a major triad, a minor seventh.
over the root. So this is a major minor seventh chord or a dominant seventh chord, right? Built on the dominant of G, so it has an uppercase, Roman numeral V, and the superscript VII there, indicating that this is a seventh chord, a dominant seventh chord. Next, I've done the same thing as previously. I've inverted that chord so that F sharp is at the bottom, the third.
Here A is at the bottom, the fifth, and here C. is the base, which is the seventh. So I have first inversion, second inversion, and third inversion, and so I indicate that appropriately with the figured bass numbers. So here I have five, six five, or dominant six five. Here I have dominant for three, and here I have dominant for two, which I could have also written as five and a low two over here, right?
And then as previously stated, a dominant 7th yearns to return to tonic. So for example, if I play this and then this, it sounds very rewarding, very satisfying. Dominant 7th going to tonic. It's a very, very common alternation of chords in music.
So, how do we do a harmonic analysis? That is, how do we assess what triads, what chords are being used in a specific excerpt of music by using our knowledge of Roman numerals, of triads, of figured bass, and the process is actually very similar to what we have seen before of identifying isolated triads. Now we're adding these triads to a specific context, to the context of a specific key, so we're adding a step to it which is we have to think of the Roman numerals, right? We have to think of these triads in relation, which scale degrees they're built in, in relation to the tonic, to scale degree one of whatever key we're dealing with.
So first up we're going to tally up all of the notes for each chord we are presented. As before, we're going to cross out whatever note is doubled, so only three or four note names should remain. Then we're going to try and arrange those notes as superimposed thirds, so we can find out what the root of those chords are. Then the qualities of the thirds, and if we have a seventh, of the seventh as well, will determine the quality of the chord. These qualities will inform us how to write the Roman numerals along with the roots that we find, right?
So if we find a major triad, that will be an uppercase roman numeral, a minor triad, lowercase roman numeral. And we have also to relate the root back to the key that we're thinking of. What scale degree is it in that particular key?
And lastly, I would add figured bass if any of those triads are inverted. So here's an example. This is a chorale by Bach. It's number 14. And it sounds like this. or at least just the very beginning of it.
Mind here that I have this one eighth note circled, right? Because that is a non-harmonic tone. That is a passing tone between B and G, two harmonic tones of these two chords.
And here we have a harmonic rhythm of... a quarter note, meaning we have a change of triads or of chords once every beat, every quarter note. You'll notice that the beat here is the quarter note because the key signature is indicating that this is four or the measure contains four quarter notes per bar. Be mindful of the anacrusis here of the upbeat, right? Just one beat and then full bars will have four quarter notes per bar.
This is in 4-4. So let's go over the steps. First we have to find out the notes of each chord.
The first one here for example we have G, B, D, G. Right? We have two G's so we end up only by crossing out the doublings G, B, and D. Thankfully G, B, and D just like that, those are already two superimposed thirds. Right, so we already have that chord in root position.
So the root is G. Now the quality of this triad is the following. G to B major third, B to D is a minor third.
That is a recipe of a major triad. So we know that this is a G major triad. We are in the key of G major.
I have given, or probably if you see an example like this in your textbook or in your life. You look at the key signature that will give you one of two options and very often you're given which option is the correct one. This could have been G major or E minor. This is in G major. So a G major triad in G major is built on scale degree 1, G.
Because it's a major triad, we're going to use the uppercase Roman numeral here, so 1. Figured bass, if necessary, since this is in root position, it doesn't need any... figured bass numbers. So this suffices. So at the beginning doing these six steps for each chord might sound like a lot of work, but actually the more you do it, the more automatically I'd say you go over these six steps for each chord up to a point where I think you'd get very comfortable just like you would reading a book, a sentence of a book and understanding what that sentence is trying to communicate.
Let's do these six steps for one more. We have here E, B, E, and G. So of the four notes, E is doubled. So in essence, we have E, B, and G, right?
If I am to arrange that into stacks of thirds, what I'll have is E, G, B, right? If I bring this G down an octave, I can... clearly see that I have E, G, B. Now to assess the quality, E to G is a minor third, G to B is a major third. So this is a minor triad, right?
Since E is scale degree 6 in G major, right, we have G, A, B, C, D, E, and this is a minor triad, so we're going to write Roman numeral 6, but at lowercase Roman numeral 6. to indicate that this is a minor triad. The lowest note, the bass here, is E. E is the root of this chord.
Therefore, we don't need any figured bass. Lowercase six will be enough in this case, right? You do that for the rest of them, you'll find out that this is the progression you have.
One, or tonic, six, three, sub-mediant, mediant. You go to the sub-dominant, and then you arrive at... a dominant seventh chord.
Look at how it works. We have D, F sharp, C and D. We have a missing or omitted fifth of this chord, right? But with experience you'll notice that sometimes the fifth is omitted, but those three notes say all that they need to say.
And then we go back to six, and then to five, Not 5-7, just the dominant triad. No note is omitted this time. Then back to tonic. This very satisfying resolution of...
dominant Teutonic. Okay. Thanks for watching next video We'll be talking all about chords in minor keys with a very similar approach to this video