- Hi, I'm Gareth and in this video,
we're going to have a little
think about this thing
called the cadential 6-4.
So we want to understand what 6-4 means
and we want to be sure we
understand what cadential means.
Well, cadential means it's a cadence.
A cadence is a kind of form
of musical punctuation.
In other words, it's something
that comes at the end
of a musical phrase,
where we have a couple of
chords that we call a cadence.
So if we go chord V to chord I,
we call it a perfect cadence.
So I'm in C major.
V-I.
That's a perfect cadence.
Or a plagal cadence is when I go IV-I.
So that's again chord
IV followed by chord I,
all these examples are in
C major for simplicity,
or I could have an imperfect cadence
that goes something to V.
Normally I to V, or II to V, or IV to V,
But the perfect cadence
and the plagal cadence
sound like kind of musical full stops,
they're the end of something.
But have a listen to an imperfect cadence.
You can hear it's the end of something,
but it's not the end of the piece, is it?
It's still left a little bit in midair.
So, if perfect and plagal cadences
are kind of musical full stops,
then an imperfect cadence feels more like
a sort of musical comma.
It's probably going to flow
on with another phrase.
Or you're going to have
the interrupted cadence,
which goes chord V followed by chord VI,
and it's a sort of a
punctuation equivalent
of a question mark if you like.
And you feel that slight surprise element
when you come to that
final chord, that chord VI.
So these are all cadences.
So that's the first
thing to be clear about
if I'm talking about
something that is cadential,
I'm talking about it in
its place as a cadence
at the end of a musical phrase.
Okay.
Let's talk about the 6-4 bit.
Well 6-4 is taking us
back to the Baroque system
of figured bass.
And the way the figured
bass worked in the Baroque,
is that you had a bass note
and the numbers told you
which notes to play above the bass note.
So, if I have C in the
bass and I've got 6-4,
well the thing is if C's
number one, what's number four?
♪ One, two, three, four ♪
Number four is F.
What's number six?
Well if number four is F,
G's number five so six is A, isn't it?
So a 6-4 above C would be C, F, and A.
And if a performer rather was reading this
in the Baroque period,
they would see C in the
bass, they'd see 6-4
written underneath the bass,
they would know that
we needed C in the bass
with a chord that involves F and A.
And you could play that in any
distribution that you want.
All of those are examples of 6-4,
because you don't have to have
six exactly above the bass
and four exactly above the bass.
You can use those spread of
notes wherever you want to.
But as long as you're using
the notes of that chord,
the 6-4 is telling you what the chord is.
But it's about intervals above the bass.
Okay, now then let's move on
to talk about this cadential 6-4 then.
Well, a cadential 6-4 is when
you have the first chord,
the 6-4 above the bass in
the way I've just described,
followed by 5-3 above the bass.
So in other words,
if I'm using that example
that I've just had.
So there was C in the bass and
we've got F and we've got A,
well the F is four and the A is six.
Well, that would move on to this chord,
because now you can see
I've got C in the bass,
E is three above the bass
and G is five above the bass.
Another thing to note as
well is that the idea of this
is not just to say it's this
chord followed by this chord,
but it's also to say
whichever part has the six,
the same part should move to five.
So it's a kind of melodic thing as well.
And whichever part has the four,
the same part should move to three.
So, say for example, I take
this example we've just given.
6-4, going to 5-3, okay?
Now let me redistribute that chord.
So here's the 6-4 chord.
And here's a 5-3 chord to follow it.
Now can you see that I've got
six in the tenor part here,
this A in the tenor,
that six is going to five,
which is G in the same
part, the tenor part,
and in this example,
I've got F in the soprano
and the F is moving down
to three, which is the E.
But I could have exactly that
in a different
distribution, like this one.
For example, where you
can see I've got six here
going to five in the alto part
and I've got four up here in the tenor
going to three in the tenor.
So it's telling us about the two chords,
6-4 above the bass,
followed by 5-3 above the bass,
but also encouraging us to
put six followed by five
in the same part and
four followed by three
in the same part.
The other thing you may have noticed,
and this is one thing that
makes the cadential 6-4
so attractive to composers,
is that the bass note
is the same for the 6-4
as it is for the 5-3.
So I had C at the bottom,
I put 6-4 above it.
When I move to 5-3,
I've still got the same bass note.
So this is why the cadential
6-4 works very nicely,
because you can maintain
the same bass note
while effectively the 6-4 is one chord,
and the 5-3 is another chord,
and we'll see how that
plays out in just a moment.
Okay, well let's put this in writing
and let's talk about a
6-4, 5-3 progression,
a cadential 6-4 in the key of D major.
Now, if I were to write this for example,
we're not really worrying
too much about note values,
but, I mean, for argument's sake,
let's have those like that.
And then, maybe we'll have the
other two parts doing that.
Now, we're in the key of D major.
I've got A in the bass.
I'm putting 6-4 above it,
and while the A continues,
it could be repeated
or just sustained as it is here.
I've got 5-3 above it.
So let's just check this out.
So we look at the first chord.
We've got A in the bass.
So in D major, a fourth above that A is D,
a sixth above is F-sharp,
F-sharp because of the key signature.
A 5-3 above the same bass note A,
three above it is C-sharp,
five above it is E.
So now I look at spreading out that chord,
here's my 6-4, spread out
you can see that the tenor
is doubling the bass.
I've got four in the alto,
I've got six in the soprano.
So the soprano's going six, five.
And the alto is going four, three.
So there's my cadential 6-4 in D major.
Now if I wanted to put
that in Roman numerals,
It would look like this.
It's Ic, followed by V, okay?
So for people who are much more familiar
with Roman numerals,
which I suspect is most people,
that's what you're talking about.
Ic followed by V.
So, does it have to be Ic followed by V?
Well, no it doesn't.
And there's another one that
is almost as common as that.
I have to say that Ic followed by V
is the most commonly found cadential 6-4,
but I'm now going to
talk about the other one.
And it's this.
So if I do another 6-4, 5-3,
it could look like this.
Okay, so there's 6-4 followed by 5-3.
But this time I've got to
think about what does that mean
in terms of Roman numerals?
Well in the key of D major,
it's IVc followed by I.
Okay.
So let's think, check it out.
We've got D in the bass this time.
That B is a six going to a five.
The D in the alto is
just doubling the bass,
that's absolutely fine.
And in the soprano I've got
four above the D in the bass
going to three.
So I put that together, 6-4, 5-3.
And this time, it's going IVc to I.
So these are the two most
commonly used cadential 6-4s.
So you can have Ic followed by V,
Or you can have IVc followed by I.
So I hope what I've tried
to explain there is clear
about well, why is it cadential,
because it's a cadence
coming at the end of a phrase.
Why it 6-4?
Because that's the Baroque
system of figured bass,
thinking about intervals
above any given bass note.
Here's the cadential 6-4 progression.
6-4 followed by 5-3.
That's telling me about the chords,
but it's also telling me
about melodic movement,
six going to five, four going to three.
And this is how it kind
of plays out, if you like,
in real life.
That you tend to go to Ic
to V, or you go IVc to I.
But both of these are
6-4, 5-3 progressions.
So, cadential 6-4.
Something well worth knowing about.
