In week four we heard about certain
cadences, we heard about perfect cadences,
which occur at the end of a piece,
and which sound very final.
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And we also heard about
imperfect cadences,
sometimes called half cadences which
are a temporary stopping point for
the music,
before the music moves on somewhere else.
For example, if we're a key of D major, we
might hear a passage something like this.
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Which obviously is not the end of a piece.
Ending there with an imperfect cadence.
But there are two other important
cadences to be considered.
First of all is the one we call
interrupted or sometimes called deceptive.
Now, if we recall our Ic-V-I cadence.
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But change just one chord.
If we change the final chord to chord six,
which is the submediant,
it sounds like this.
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So, very different.
Let's compare again.
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And I think you'll agree that
both the words interrupted and
deceptive describe
the effect here very well.
The music obviously must continue.
I'll play you another example.
That one was in D major, but
let's have one in G minor.
Here's a ic-V-i in G minor.
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And here's an interruptive
cadence in G minor.
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Moving to chord 6, where the music
demands it, that it continues.
The other cadence we need to know about is
called the Plagal Cadence sometimes called
a Hymn or
Church Cadence because it's the one you
often hear in a amen at the end of a hymn.
And it's chord four to chord one.
The sub dominant to
the tonic in F major here.
This is a cadence that was used a great
deal in church music in medieval and
renaissance period but subsequently
too and interestingly we find it
pops up quite often in newer
music in blues and rock and pop.
And, a number of examples can
be found in Beatles songs.
For example,
With a Little Help from My Friends,
the last three chords of which are
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The last two of these making
up the plagal cadence.
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Four one.
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And interestingly here,
there's an extra flavor added because of
the mortal influence of
the third last chord.
The third last chord is based
on the flattened leading note.
Here is a scale of E-major.
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Leading note,
this time with the flattened leading note.
Which gives us what we
call the Mixolydian mode.
And if you base a chord on that D,
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It gives you the third
last chord of that song.
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And interestingly it's
also used in 'Hey Jude'.
Here's the final chords of 'Hey Jude".
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With the Plagal Cadence says the last two,
and the Mixolydian chord, the third last.
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