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Step 1 - Identifying Modulations Related Keys The first thing
that you need to do when going through a chorale is to identify the
modulations in key. This is an easy process, as Bach will only tend
to go to closely related keys. This means that the only keys you
should use are the Tonic, Relative Major/Minor, the Dominant and
Subdominant and their relative Major/Minors. Remember that in a
minor key Bach uses the melodic minor, because whilst we are
looking at functional harmony, and you may imagine this would
involve the harmonic minor, we are looking at four separate melody
lines. Below are two examples of key charts that you should write
out for any Bach chorale you complete; one is in a major key and
one in a minor key. Fig 1. Major Chart Fig 2. Minor Chart
When you have written out these diagrams it is also advisable to
write out the accidentals that you are looking for to indicate that
the melody line has modulated to another key. For example:
Tonic (C Major) Subdominant (F Major)
Rel. Minor (D Minor) Rel. Minor (A Minor) Dominant (G Major)
Rel. Minor (E Minor)
Tonic (D Minor) Subdominant (G Minor)
Rel. Major (Bb Major) Rel. Major(F Major) Dominant (A Minor)
Rel. Major (C Major)
Tonic (C Major)
Subdominant (F Major) Bb Rel. Minor (D Minor) Bb B and C# if the
proceeding note is higher.
Rel. Minor (A Minor) F# and G# if the proceeding note is higher.
Dominant (G Major) F# Rel. Minor (E Minor) F# C# and D# if the
proceeding note is higher.
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Exercise 1 Fill in the following related key diagrams:
Bb Major F Major
Eb Major A Major
E Minor C# Minor
B Minor F Minor
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Identifying Modulations Within Phrases Whilst this method of
working out which key a chorale has modulated to works in most
circumstances, there are other things to take into account when
looking at a chorales modulations, especially as certain phrases
can appear to be in many keys. Take the following phrase for
example:
This phrase at first glance appears to be in C major. However,
because the phrase does not contain any Gs or Fs we cannot tell if
the phrase is in A minor. With this in mind we need to look at the
end of the phrase. A majority of the time in a chorale we are
expecting to see the supertonic followed by the tonic at the end of
a phrase (2 -1). If the last two notes do not do this in any of the
keys that you are expecting, then check if the last two notes could
be from chords I and V, for example:
There are no accidentals in this example so it appears at first
glance to still be in Bb major, however the final cadence could not
be the chords F and Bb as A and C do not appear in the chord of Bb.
There are also no Ebs in this example, therefore the phrase could
be in either F or Dm, if we check the last two notes it could still
be in either key, as we could put the last two chords as either Am
Dm or C F. However, because the 7th would be falling in Dm it is
much more likely to be in F major, as you would expect the leading
note to rise at a cadence.
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Exercise 2 Write in the most likely key for each phrase in the
following chorale exercises: i)
10
*P40427A01016*
Technical Study 2
Add alto, tenor and bass parts to complete the following in the
style of J. S. Bach.(40)
!
!
!
""# $$ $$ $ $$ $$ $ $$ $ $ $ %
&$ $ %'# $
$ $$ $ $$ $ $$ $ $ $$ %%
3!
""# $ $ $ $ $ % %&
(
'#
5!
""# $ $ $ $ $ $ $ %
&
'#
Key:
Key:
Key:
-
11
*P40427A01116* Turn over
7!
"!" # # #" # # # #" $
%
&"
9!
"!" # # # # # # # # # $
%
&"
11!
"!" # # # # # # # # $
%
&"
Key:
Key:
Key:
-
ii)
10
*P38655A01016*
Technical Study 2
Add alto, tenor and bass parts to complete the following in the
style of J. S. Bach.(40)
3
5
Key:
Key:
Key:
-
11
*P38655A01116* Turn over
7
9
Key:
Key:
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Types of Modulation In a chorale there are three ways by which a
modulation can be achieved. The one common type of modulation is
phrase modulation. Phrase modulation is where the chorale has a
whole phrase in one key. The next phrase may be in a different
(related) key without any preparation, because the previous phrase
ended at the cadence. This type of modulation is the same as the
modulations you identified in the previous exercise. Usually the
new phrase will start with the dominant of the new key to help to
reinforce the harmony, although chord I can also be used, but it is
not as strong. Another common type of modulation is using a pivot
chord in the middle of a phrase to change key. A pivot chord is a
chord that is common to both keys. For example if you wanted to
modulate from C major to G Major you could use A minor as a pivot
chord, as it is chord vi in C major and chord ii in G major. A
pivot chord is usually followed by chord V of the new key, as this
helps to reinforce the harmony.
Some useful pivot chords to know are: Major Pivot Chords Minor
Pivot Chords Subdominant: ii=vi (Dm is ii in C and vi in F)
Relative Minor: ii=iv (Dm is ii in C and iv in Am) Dominant: vi=ii
(Am is vi in C and ii in G) Subdominant: iv=i (Dm is iv in Am and i
in Dm) Relative Major: iv=ii (Dm is iv in Am and ii in C Major)
Dominant: i=iv (Am is i in Am and iv in Em) The final type of
modulation is an abrupt modulation. This type of modulation jumps
straight to chord V of a new key without any pivot chord, and it
sounds abrupt! This is the least common of the modulations found in
chorales and is used for effect, usually to reflect the text of the
chorale. Exercise 3 Identify the pivot chords used in the following
modulation:
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Identify the key changes in the following chorales; can you spot
what type of modulation has been used?