Hello, this is Mike Hayes and welcome to our video on music
theory in particular our focus on this video will be about the
tritone or flat five substitution.
We'll be discussing three things: firstly, what it is; secondly, how
it works; and thirdly, we'll show you a couple of applications of
the tritone substitution.
So firstly, let's have a little bit of a talk about
what it is.
in jazz harmony, the tritone is both part of the
dominant chord and its substitute dominant (which is also known
as the sub V chord).
Because they share the same tritone, they are possible substitutes for one another.
This is known as a tritone substitution.
The tritone substitution is one of the most common chord and improvisation devices in
jazz; but we don't want to restrict his conversation to just jazz;
it's also used (the tritone substitution) is also used in sophisticated
pop groups in commercial recordings; ah, I'm thinking about
groups like Steely Dan.
And we'll be having a look at how Steely Dan actually
applied this flat 5 substitution and ah, they applied it to a
very common chord progression to create a completely new, fresh
sound just by using this one music theory concept.
Ok, flat 5, tritone what does these terms mean?
Well, they're a way of measuring musical distance ... what musicians
call 'intervals'; and in music theory we use these terms to
describe the distance of one note to the next; it's part of the
language that musicians use to communicate musical ideas to each other.
Now, the particular musical interval that we're discussing
on this video can be named four different ways, in fact,
it can be named more than four different ways, but there's four
common ways that musicians refer to this musical interval.
And the four ways are: tritone, flat 5, Augmented 4th and Diminished
5th all these terms are interchangeable however when I'm discussing
this interval I'll be referring to it as either a flat 5
or a tritone.Ok, so that takes care of what a tritone is; let's
have a look at how it works.
One of the keys to a really good chord progression is the
control of consonance and dissonance, and essentially, dissonance
in music creates tension which equals motion; consonance equals
resolution or rest.
Now to help you understand this tension and resolution and the flat 5 ah, concept and
so on I'm just going to start with some examples and to begin with
I'm going to use as a reference point the note E; that's the sixth
string open on my guitar ... and I'm just going to talk about
the overtone series for a moment, I've covered the overtone series
in great detail on another video but I need to touch on one or
two aspects of it to ah, clear up how this flat 5 ah, substitution
works.
Ah, essentially, when we're hearing a note, we
think we're hearing just one sound but what really is happening
is we're hearing a combination of notes ah, so our sound that
we're hearing is really a compound sound.
So when I'm playing this note E; I'm going to call that the fundamental tone, now
the next note in the overtone series is an octave higher; so we
have the fundamental tone, E we have it's octave (E) and the next
note in the overtone series is the fifth, the note B. So when we're
talking in terms of consonance and dissonance the most consonant
note would be the fifth.
And now it's time to have a look at a number of different
ways to locate the flat 5 note on the guitar fingerboard and also
to explain several of the music theory terms we mentioned earlier
on the video.
Here's an easy way to visualize the flat 5 concept
on the guitar fingerboard again, I'm going to use the note E as
my reference note as we've just discovered the most consonant
note after the fundamental tone is the fifth and musicians call
this interval the 'perfect' fifth, in contrast
to the perfect fifth we're looking to find the maximum amount of
dissonance.
When we look at the guitar fingerboard it's easy to
see how this works: an octave is made up of 12 semitones and since
the guitar fretboard is divided up in semitones, each
fret marking out a semitone, it's easy to find the halfway point;
which would be at fret six, and this is where the flat 5 note
is found, so the flattened fifth of E is B flat, and it's right
next door to the perfect fifth which would be B that's found
on the seventh fret.
So to sum up, to find the flat 5 note using an open string as a
starting point we find the midway point or the halfway point of
the octave and that's were we find the flat 5 note e.g., if we
began on the note B (the second string open); and looking at the
octave being 12 frets, the flattened fifth of B would be found at
the sixth fret which would be the note F. Another interesting
thing about the flat 5 note is that it's also referred to as the
'blues note'; so it's the extra note that's added into a minor
pentatonic scale to create a blues scale.
Let's review: the flat 5 is the midpoint of the octave, there's 12
semitones to an octave and the flat five is the sixth semitone.
Musicians use the flat five note to create dissonance and as
we spoke about earlier on the video it's this dissonance that gives
motion to the music; so with the flat 5 note in the midpoint of
the octave it's essentially like a 'tipping point'; that can
help create the greatest amount of tension and the greater
the amount of tension the more dramatic or powerful the resolution.
The flat 5 note can also be referred to as the blues note and
when we add this flat 5 note to a minor pentatonic scale we create
the blues scale.
Now if you want to hear this flat 5 note in action
you might want to listen to the opening notes in Jimi Hendrix's
'Purple Haze' where the flat five note, (the B flat) is
played in octaves: low B flat, high B flat, low B flat, high B flat
... I hope you've enjoyed this video and we'll be developing
all these ideas further on the next video, this is Mike Hayes
and thanks for watching