| BAR |
WHAT HAPPENS |
COMMENT |
| 1-10 |
First subject presented in the tonic key (B-flat
major). |
|
| 10 |
Re-statement of opening an octave lower, but soon
deviating to introduce an |
|
| 12 |
E-natural in the RH |
The E-natural introduces a C major dominant 7th
harmony (V of V in B flat ). This is the start of the modulation to F major
(the dominant) for the second subject. |
| 13.4, 14.4 and 15.4 |
The RH has a falling group of semiquavers at the
end of each bar. |
Even before the second subject has arrived, Mozart
is developing and playing with the opening shape of the first subject. |
| 17.3 |
A B-natural occurs in the LH |
The B-natural introduces a G major dominant 7th
harmony (V of V of V), strengthening the move away from the tonic key. |
| 22 |
Arpeggio figuration of a C major chord. |
This is confirmation of a new dominant chord as
preparation for the second subject in F major. |
| 23-30 |
Second subject, in the new key of F major. |
Although this is a new theme there are some links
with the first subject; bar 24 is rhythmically identical to bar 1. The offbeat
crotchet rhythm from the first subject (RH bar 5) occurs in the second subject
at bars 25 and 29. |
| 31 |
Repeat of second subject which, after five bars,
tries to move away from F major to |
|
| 35 |
G minor, but returns after only one bar. |
|
| 38-63 |
Numerous Ic-V-I cadences in F major, on a small
scale such as the end of bar 45, or drawn out to cover two complete bars
(57-58). |
Extended affirmation of F as the new tonal centre,
despite harmonic devices such as the rising sequence in 43-44, the cycle of
fifths in 47-48 and the passing V-I cadences in B flat in 50-51 and 54-55.
There is little of thematic relevance here, although perhaps the rising RH 3rds
in 50-51 and 54-55 relate back to (and develop) bar 12. |
| 64 |
The development section opens with the first
subject motif in F major. |
The three-quaver rhythm that ends bar 1 is
developed in the RH at the end of bars 66, 67 and 69 |
| 71 |
The expected perfect cadence in F major is
replaced by a plunge into f minor. |
The use of the dominant minor, together with a
rapid Alberti bass, injects drama into the music. This is heightened by
the sudden RH leap in bar 73 onto a top F (the highest note on Mozart's piano).
The dark colour of the following section is maintained by the transitory use of
other minor keys including c minor (bar 75), e-flat minor (bar 76) and g minor
(bars 80-86). |
| 71-93 |
Thematic development of two main ideas; the
opening of the first subject and the falling LH shape from bar 30. |
The first subject is divided into its component
rhythmic cells which are then incorporated into the RH's phrases. For example,
the rhythm on the first two beats of bars 75 and 77 show a development of the
cell which opens bar 1. Also, the last beat of the RH in bar 80 clearly
imitates the falling anacrusis which starts the sonata. A more explicit
development of the first subject can be seen in the RH of bar 79, where, apart
from transposition of the theme to fit a different harmonic scheme one can
observe intervallic augmentation in the stretching of the leap between
the 3rd and 4th beats from the original perfect 4th to an octave.
The LH falling motif from bar 30 can be seen in the RH of bars 72 and 77, with
extended versions occuring in bars 81-82 and 83-84.
Bars 87-90 develop the appogiaturas that are found at bars 1.1, 2.1, 3.1
and 4.1 |
| 87-90 |
The music focuses around an F major dominant 7th
chord. |
Mozart is preparing F as a dominant pedal
to herald the recapitulation in the home key of B-flat major (despite a hint at
b-flat minor through the use of a D-flat in the RH of bars 90-91). |
| 94 |
Beginning of recapitulation, which is an exact
copy of the exposition until |
|
| 105 |
the introduction of an A-flat in the RH takes the
music off briefly in a new direction. |
Mozart is still introducing new bits of
development, even in the recapitulation. This is necessary because the original
move to the dominant key in the exposition must be avoided here if the movement
is to retain the traditional tonal balance of a sonata structure. The music
veers towards E-flat major (bar 106), c minor (bar 107) and F major (bar 109)
before settling back in the tonic of B-flat major in bar 110, from where the
recapitulation continues (corresponding to bar 15 of the exposition). |
| 119 |
The second subject appears in the tonic key. |
The following music up to bar 143 is almost an
exact transposition of the original except for a few minor details such as the
RH in bar 126 (compare to bar 30). |
| 143 |
Further development over a cycle of fifths
harmonic progression. The alternate wide melodic leaps of 6ths and 7th found
originally in the second subject at bar 25 are developed in a falling sequence
(143-146) and then by intervallic diminution (147-149). |
Mozart made no real reference to the second
subject throughout the development section, so this is a final opportunity to
explore some of its more characteristic shapes, albeit in a fairly subtle
manner. |
| 152-165 |
Coda, in B-flat major, corresponding exactly to
that of the exposition (bars 50-63) except for a few changes to the RH
semiquaver passagework. |
The most interesting deviation from the exposition
is in bar 162, where an exact transposed replica would take the RH up to a top
G. This note did not exist on Mozart's piano, so the bar had to be re-written
to compensate for this. |
