Here we're going to talk about the diminished
fifth. Let's look at the major scale. First
note of the major scale, second note, third
note, fourth note, fifth note. Now again a
diminished fifth is just a half step below
or one fret below the fifth. Instead of calling
that a minor fifth we call it a diminished
fifth. Now this is also the only place on
the neck where you could call it a sharp something
or an augmented something. You could take
the five and raise it up a fret, which we'll
see in a minute, we call it an augmented fifth
or we could take the four and raise that up
and call it an augmented fourth. However,
that's pretty rare but you could say sharp
four and flat five. We will see that when
we get to chords but you could refer to this
either as a flat five or a sharp four. It's
also known as the tri-tone because it's right
in the middle. If you divide an octave into
three parts, you've got the root, the octave,
and this note that falls right in the middle.
Now you've got this shape down one string
up one fret until you get to the B string
stretch it out by one and then it's back to
the same from the B to the E string.
