I've been looking through the forums today and what I've noticed is that the idea of

looking at intervals and finding out what they are and how to fully describe them.

It's one of the areas that I think some people might benefit

from having some extra assistance with and some, some course of explanation.

So what I'm going to do here is I'm just going to flash up some

intervals on the screen, I'm going to talk through, roughly, the way that I would.

Approach working out what they are and describing them

and hopefully just that this, this will be useful for

some people because it will allow you to almost see

the process happen in action and watch it top through.

Now what I'm using here on the screen is

musictheory.net, I've just got to close up of the.

Application.

I would say check out this website because it is a fantastic one and

it'd be really useful for you practicing

some of the things that we're talking about.

So, as I said I'm just gona really quickly chat through a

few examples for you and give you some tips as we go.

Okay so first thing I'm going to do is I'm going to look

at the clef and I'm going to notice it's the base clef.

Which means that this lowest note here is a D.

Come up from our lowest note we get D, E, F, G.

One, two, three, four.

So this is a fourth of some description.

Now, what I always say to people.

Is to look at the lowest note and imagine that

you're in the major key of which this is the tonic.

So if you look at the lowest note here, we've got a D.

So what I want you to do is just imagine that you're in the key of D major.

So if you're in the key of D major, you'd expect

to find an F sharp and a C sharp and nothing else.

So in this case we've got a G.

We're looking for D to G-natural.

G would occur in the key of D-major.

Now, for what we're going to call this, a perfect fourth.

Let's click the button here and find out if we're right.

[SOUND] Correct.

Perfect fourths.

So the lowest note here we've got is D.

Again, just by coincidence.

So what we're going to do is we're going to carry up four.

One, two, three, four and the [INAUDIBLE] G.

Now this is just sheer coincidence that we're

getting a similar interval to the last one.

And in the last one you said it was D to G.

There were no other sharps and flats.

So therefore D to G was our perfect fouth.

Now we've got a D to a G, but this time it's G sharp.

So we've got D to G sharp.

Now, because this upper note's been sharpened.

It's make this note a semitone higher.

And what that serves to do is stretch them,

the gap's a bit bigger now between the bottom one.

And the top one.

So what we've got here actually is what looks like a perfect fourth, if

it was just D to G, but it's been made larger by one semitone.

So perfect if made larger by one semitone, just going to

click on augmented fourth here and see if we're right.

Okay, so this time what we're got in an A to an F.

Now, we do have an F sharp on the

key signature, but because we've got an F natural here.

This natural sign cancels out the sharp, so what we

can say is this is an A to an F.

Let's out it out numerically.

One, two, three, four, five, six.

An A to an F is a sixth of some description.

Now if we were in the key of A major, we

would expect to find an F sharp, C sharp and G sharp.

Right so if this was to be A to F sharp, what we

would find out is that this is a major sixth, in fact it isn't.

There's natural, F natural is a semitone lower than

the F sharp that we expect in the major key.

So, what we can say then is that it's a major interval that's

been made smaller by a semitone and that gives us a minor sixth.

Let's click this and see if we're right.

Fantastic.

Okay, so in this case we've got an E to C flat.

Let's work through this one then, because this could be quite interesting.

We've got A, B, C, so that's one, two, three.

We know it's a third of some description.

Now, if we had, If we will imagine that we're in the key of the lowest note,

so A-major, we would expect to find an F-sharp, C-sharp, and G-sharp.

So this is a C flat.

But not only is it a C sharp that's been

made lower by one semitone, taking it to a C natural.

This has been lowered again, talking it to a C flat.

So if we had a C sharp, it would be a major

third, lower again to C natural, it would be a minor third.

And lower again to a C flat, that's a

minor third that's been lowered by a half step.

And a minor third that has been smaller by a

semitone or by a half step, is a diminished third.

Okay so let's have a look at this one, this is an

F, because remember we're in the bass clef now, to an A flat.

Now, if we were in the key of F major.

Remember we're [INAUDIBLE] we're in the major key of the lower two levels.

Then we would expect to find a B flat and that's all.

Now, in this case we've got an A flat.

So we would expect to find an A natural in the key of F

major and that would be a major third because we've got an A flat.

It's been lowered by a semi-tone.

Got an F to an A flat.

So that's no longer a major third as it would be if we had an F

to an A, if we lowered by a semitone so what we got is minor third.

Okay, so this is one of the examples.

Refer to that we can't really imagine within the key of the lower note.

The reason for that is that our lower note in this example

is a B sharp and there isn't a key of B sharp major.

So what I'm going to say is, when we get an example like this,

just ignore the accidental and ignore the key signature and imagine that we're in.

A key of B major.

So you can imagine that this lower note is a B

natural and therefore we will be in the key of B major.

Now B major has F sharp, C sharp, G sharp, D sharp and A sharp.

So we would expect this to be a D sharp.

So let's just go back one step then and

count the the number together with the numeric code

description of them to [UNKNOWN] code BS1, CS2, DS3

so this is the third of some of the description.

I'd rather say if we ran in the key of B major we do

expect that to be a D sharp, because that's part of the key signature.

If that was a D Sharp, that we be a major third.

Okay.

However, this is only a D natural, so B still

ignoring the sharp for just now, B to D natural.

Is a minor third.

Now because the lower note here has been raised by a semitone,

what that does is that effectively makes the interval smaller by a semitone.

The gap has been closed, making the interval smaller.

So would be a minor start if it was B to D, but what we've got is B sharp to D.

So it's actually a semitone smaller than a minor

third, and we refer to that as as diminished third.

Okay so what about this interval then.

We've got a B flat, to D flat.

Now if we were in the key of B flat major.

Again that's going to back imagining that we're in the key.

Of which the lower note is the tonic B flat.

You'd expect a B flat and an E flat.

Nothing else.

And what we find here is that we've actually got a D flat.

So if this a B flat to D natural, it would be major third.

But because it's a B flat to a D flat, which is a semitone smaller.

That means to interval is a semitone smaller than the major

third would be, so what we get is a minor third.