[MUSIC]
That little piece of music,
that little excerpt was from Bach,
sonata number 1 in G minor, presto section.
It is a great example of a concept called octave displacement,
which Bach used a lot and I think is
a great idea for creating really unique sounding lines.
I'll play it again. [MUSIC] That was actually a continuous scale,
but you can't tell because of where it jumped.
If I were to start on that A,
[MUSIC] but start high enough to play it continuously,
[MUSIC] that's the note.
That's the same note. It just was continuously going down a scale.
But what happened was he starts low,
[MUSIC] instead of high [MUSIC] and then he says,
"I have enough room to jump up the opposite interval I was going down."
That's the general idea for octave displacement.
If the interval was going down,
which he wants to go to a G. [MUSIC] He said, 'Well,
instead of going down to the G,
[MUSIC] I'll go up to the G." Then from the G,
he plays the four notes that go in line with that.
[MUSIC] Once he gets to the D he says,
"Well, instead of going down to the C,
[MUSIC] again, we go up to the C [MUSIC] the opposite interval,"
so down a second is the same interval is up a seventh.
We have this neat thing of symmetry with intervals.
If you want to find the opposite interval,
the remaining number is always going to equal nine in the end.
If it was a two,
you add seven, that's a nine.
If you were going down a third,
you add a sixth,
and that's nine, so you go up a sixth instead.
It works the opposite way too.
If you want to go up a second,
you would go down a seventh.
If you wanted to go up a fourth, you go down a fifth,
and it's the same note just in the opposite register.
This is just a great idea in changing direction,
getting ideas for making your same melody you might have had,
giving it some more life or adding to it a little bit.
[NOISE] Here we have, again,
the [MUSIC] and then jumps up to the C. [MUSIC]
Now, it would normally go down to the F,
but he goes up to the F,
[MUSIC] and would normally go down to the B flat,
but he goes up to the B flat.
[MUSIC] There it is,
a continuous scale that is made to ascend by flipping the interval every four notes.
He plays for notes at a time except for the first one.
[MUSIC] He goes to first one then he plays four notes,
[MUSIC] then flips to the next phrase to the next four notes [MUSIC] to the next four.
Then he has five left to finish the measure.
[MUSIC] Also on a side note,
Bach was playing those over the bar line because this is all in 3/8, so it's going 1, 2,
3, 4, 5, 6, or 1, 2, 3, 1, 2, 3, 1, 2,
3 over and over again and these things continuously go over the bar.
[MUSIC] It's a neat little phrase.
Here's a way to start breaking down
some shapes on the guitar that will give you seconds and sevenths.
One little exercise you can play is to find
three notes sequentially on the top string somewhere high.
[MUSIC] That's the E,
F sharp G of my G scale.
To give that the most extreme difference that you possibly could,
you take the [MUSIC] F sharp that you went up to and go [MUSIC] down to it instead.
[MUSIC] There's one option. Same thing.
Then if I want to make it even more extreme,
make all three of them in a different register,
[MUSIC] that's your G there.
So you get [MUSIC].
That's a neat little thing.
Instead of ending your scale,
[MUSIC] you can go [MUSIC].
Take a look at all of the different ways and examples that I put together
which demonstrate this octave displacement idea and have some fun with it.