- Hi.
Well, today we've got a
little quiz on intervals.
Something that every musician
really needs to know about
at some point.
So, on the board I've
got a number of intervals
for you to name that involve
use of the treble clef,
the bass clef, the alto
clef, and the tenor clef.
So you may want to pause at this moment
and just see how you get on
or feel free to stick with me
if you want to while I just go through
and explain the answers to
each of these intervals.
So, just a quick recap on
how we calculate intervals
or what I perceive to be the
best means of doing so anyway,
which is this.
First of all, work out the
number of the interval,
so we look at the first one.
This is a G to a C.
What the number is, is by
counting the G as number one,
G, A, B, C, confirms
that this is a fourth.
So the first thing to do
is get the number of
the interval in place.
The second thing to do then,
is to work in the major scale
of the lower note.
So, if the lower note's G,
well what's the fourth note of G major?
The fourth note of G major
is C, so in other words,
C is in the major scale
of the lower note, the G.
And remember, if the upper
note's in the major scale
of the lower note, if it's a
fourth, a fifth or an octave,
it's a perfect interval.
And if it's anything else,
it's a major interval.
An only when the upper note
isn't in the major scale
of the lower note,
do you then have to kind
of tweak things from there.
And we'll come to that in due course.
But the first one is a perfect fourth.
G to C.
One, two, three, four.
The C's in the major scale of G.
So it's a perfect fourth.
And that's the sound of the interval.
G to C, or if I play them together,
there's the sound of a fourth.
And while you're learning
to recognise intervals,
it's a very good thing to get
them aurally centred as well
so you get some idea
what these particular
intervals sound like.
Okay, interval B.
So we're in the bass clef.
We're working with A-flat at
the bottom up to F at the top.
So don't worry about
the A-flat for a moment.
Some kind of A to some kind of F.
What's the number?
A, B, C, D, E, F.
So it must be a sixth.
So always commit to the number first,
so you don't get persuaded
somewhere down the line
that it might be some kind of
fifth or seventh or something.
That's definitely a sixth
because it's some kind of A
to some kind of F.
Okay.
A-flat major.
What is the sixth note of
the scale of A-flat major?
Which is why it's also
a good revision of keys
and knowing what key signatures
are for particular keys.
A-flat major, the sixth note is F.
So F is in the major
scale of the lower note.
So if the interval is the sixth,
then it must be a major sixth.
Remember, fourth, fifth,
octave, are perfect,
but the second, the third,
the sixth and the seventh,
the other ones, have to be major.
So if that note is the
sixth note of A-flat major,
it's a major sixth, which it is.
Great, what does it sound like?
A-flat up to F.
So there is a major sixth.
Or if I play them together,
That's what it sounds like,
so clocking the sound of that as well.
Interval C is interestingly
in the alto clef.
So it's a chance just to
revise your alto clef as well.
Remember in the alto clef,
the line in the middle
of the stave is middle C.
You see where that bar is on the clef.
So that's middle C.
So if that's middle C, this note must be B
and then you can work out
where you're going from there,
C, D, E, F.
So it's B up to F.
So first of all, let's have
the number of the interval.
B, C, D, E, F.
It's a fifth.
So before you decide
what kind of fifth it is,
you can commit to the fact
that it's definitely a fifth
and nothing else.
Now, B's at the bottom.
Let's think in B major, we know
we're dealing with a fifth,
so what's the fifth note of B major?
Well, B Major has got five sharps,
and the first of those is F-sharp.
So in other words,
if this interval happened
to be B to F-sharp,
it would be a perfect fifth
because F-sharp is the
fifth note of B major.
So now we're looking at this thinking,
well that's fine but this
isn't F-sharp, it's F-natural.
So the question is, is this
interval bigger or smaller
than a perfect fifth?
So if a perfect fifth is B to F-sharp,
we're now looking at B to F.
Can you see what I've done there?
B to F-sharp.
B to F.
So my hands are closer
together by one semitone.
In other words, the interval,
the distance between the two
notes is a semitone smaller
than a perfect interval should be.
If you're a semitone smaller
than a perfect fifth,
you're going to have a diminished fifth.
So this is a diminished fifth.
So a semitone smaller than
perfect is diminished.
A semitone bigger than
perfect is augmented.
So that's a diminished fifth.
It's got a very
distinctive sound actually.
B up to F.
Play that together,
you can hear it's a very
distinctive sound isn't it?
Sometimes called a tritone
because it comprises three tones.
One, two, three.
So there it is.
Diminished fifth.
Okay, interval D is in the tenor clef.
So the tenor clef works
like the alto clef,
it's just that it's a bit higher,
so this time C isn't in the
middle, it's on line four.
And it's always middle
C, just for reference.
So there's middle C in the tenor clef,
so what are we looking at here?
D because it's just one above that.
D, E, F.
So it's D up to F.
So what's the number of
the interval, D, E, F.
It's a third.
Then I'm going to think,
if the bottom note's D,
I'm going to work in D major.
What's the third note in D
major, the answer is F-sharp.
So, let's do this little game again.
D, F-sharp is a major third.
But D, F-natural,
my hands are a step closer
together, aren't they?
So in other words, the
interval is slightly smaller.
One semitone smaller than a major third.
Okay, now if you have a major interval
and you make it a semitone
smaller, it becomes minor.
Make it another semitone
smaller it becomes diminished.
If you have a major interval
and you make it a semitone
bigger, it becomes augmented.
So, D to F-sharp should be a major third.
This is D to F-natural,
it's a semitone smaller
than a major interval,
so it's a minor interval, minor third.
This is what it sounds like, here's D.
Here's F.
Put them both together, minor third.
Okay, for interval E, we're
back into the bass clef.
Now, quite a wide interval this time.
So what've we got?
We've got G at the bottom
and we've got B at the top.
Two ways of describing this.
First of all, you can count up.
You can go one, two, three, four, five,
six, seven, eight, nine, ten.
And you can say that's a tenth.
Or you can say any interval
that's more than an octave
is something we call a compound interval.
So the first thing to write down
if you're naming it on
paper is the word compound.
Then, you can either take
the top note down an octave
or you can bring the
bottom note up an octave
and say what's the interval.
So if we do that, we can
either talk about a tenth,
or we can say well let's bring
this B down an octave to B,
and then I'm going to go
G, A, B, so it's a third.
It's not a third, it's a compound third.
And to be precise, it's a
compound something third,
which we're now going to work out.
So, if it's G to B, a
compound something third,
in G major, the lower note,
what should the third note be
and the answer is B.
So B is the third note of G major.
Therefore, it's a major third.
So this is a compound major third.
Here's G.
Here's B.
Put them both together,
there you've got your
compound major third.
Because it's a major third,
a compound major third,
you could also call it a major tenth.
And that would be perfectly in order.
Interval F.
We've got A at the bottom in
the treble clef going up to G
at the top.
So what's the number of
the interval, the distance?
One, two, three, four, five, six, seven.
Remember, always count the
lower note as number one.
So that's a seventh.
Well what kind of seventh is it?
A major, the seventh note
of A major is G-sharp.
So if it were A to G-sharp,
that would be a major seventh.
So A to G-sharp, major seventh.
What's happened here?
G-sharp is not G-sharp, it's G-natural.
So my interval is a semitone
smaller than a major seventh.
So semitone smaller than major is minor
so therefore, A up to
G is a minor seventh.
This is what it sounds like.
A up to G.
Put the two together.
There's your minor seventh.
And finally, let's have
a look at interval G.
We're back in the treble clef.
We've got E at the bottom,
A-sharp at the top.
Calculate the number first.
One, two, three, four.
So it's a fourth.
Work in the major scale of the lower note.
E major.
What's the fourth note of E major?
A-natural.
So, E to A-natural would be
a perfect fourth remember
because fourths, fifths,
and octaves are perfect.
All the rest are major.
So E to A is a perfect fourth.
But this isn't E to A, it's E to A-sharp.
So what's happened this time?
My hands have got a
semitone further apart.
So what's one semitone bigger
than a perfect interval?
An augmented interval.
So that is an augmented fourth.
Here's E, here's A-sharp.
Play them together and it's
another one of those tritones.
One, two, three.
You remember we met one back here.
And it's interesting isn't
it that a diminished fifth
is the same sound as an augmented fourth,
even though one's a
fifth and one's a fourth.
So there it is, your augmented fourth.
So, if you didn't know about intervals,
I hope that's kind of got
you into it slightly quickly.
We've got courses out
there in our theory series
that will go into this in much more detail
and explain it fully for you.
If you're wanting to revise
the interval knowledge,
well I hope that's been a
useful exercise in doing that
and if you needed to have
a really secure method
for learning how to identify intervals,
I hope I've also demonstrated that.
And whatever you do, if you
can do them theoretically,
also learn to recognise intervals aurally
because that is of great
assistance to any musician.
