The 2nd movement of the Mozart k310 Piano Sonata resembles standard sonata form in many ways. It opens with a first theme in F (same as key signature). The theme is four bars long; two bars of antecedant, two bars of consequent.
Mozart then starts the first theme again with a 32nd note run pick-up instead of the 16th note arpeggio pick-up in the the begginning of the piece so we are prepared for variation in the second statement of the first theme. He then continues the theme with variation until the consequent phrase which is completely different from the first consequent phrase. This new consequent has not only faster rythmic movement but also compressed harmonic rythym. This tension prepares the listener for the textural shift that is about to occur.Order now
The Bridge begins with 16th note arpeggios in the bass, a contrast to the quarter note dominated bass of the first theme. Unlike a typical bridge section which modulates far from the original key, this bridge just moves from I to V7 for several bars before going to ii. Then, rather than using the ii in a familiar ii-V7-I cadence, the ii is arpeggiated for an entire bar in the melody. This is further obscured by the chromatics used in the arpeggio, a half step movement to each chord tone.
The next bar returns to I without a real cadence and then quickly moves to V. We are now at the second them and it does begin in C (V, the way most second themes begin), but C has not really been tonicized. C still sounds like V. This is solved by the ‘b’ natural in the pickups to the second theme, implying the new key center with a leading tone in place of a true tonicization from a cadence.
The second theme, like the first, has an antecedant and consequent phrase. However, they are each only one bar rather than two as in the first theme. They are then repeated without variation but in another register with a trill in the treble. There is then a sonata form rounding off of the second theme for three bars.
The closing follows the second theme and is quite long in this piece. A short repeated figure in the first bar and a half is ended by what sounds at first like modulation, but does not actually continue to another key. It instead rounds off back to C and the first short repeated figure enters again, this time with ornamentation. This time the figure ends when it arrives at a ii chord and there is a new texture.
A long d minor melodic scale in the treble ends in the next bar on a I chord and is echoed by a G major scale in the bass. The I chord confuses the tonal direction becasuse the listener expects the ii to be followed by V and then I. This is even more confusing because the scale that accompanies the I chord implies V (the chord the listener wants to hear). The next bar rounds off this cadential prolongation (ii-V-I) but the exposition does not yet end.
The arrival to I does not occur until beat three of the bar. The first two beats create even more prolongation as they nearly modulate. And even after this, the exposition is not done. There is a two bar codetta (a one bar figure played twice, the second time with variation) before the strong V7-I cadence with a C pedal tone.
This is the first very strong cadence since the start of the closing material.
Since the cadence at the end of the exposition is to C without any hint of F as a tonic, the Developement begins in C. In fact, it is clearly in C as its pick-ups are a C arpeggio and the first bar looks and sounds like I and shows no indication of a ‘Bb’ or any other scale alteration. The opening of the developement is also a textural change but seems to resemble old material in its melody.
Both the first theme and the second theme have similar figures to the new material.
The developement starts with tonal movement in each of the first two measures, I in the first measure and ii6 in the second. In the third bar the harmonic rythym increases with a I64 for the first two beats and a V7 in the third beat. The next bar is a I6 followed by a bar with a harmonic change each beat: ii6, I64, and V7.
Already there is tonal ambiguity. Twice a ii chord has returned to I intstead of continuing to a V chord or a substitute. And at the end of the 6th bar of the development a V7 has been set up.
The V7 does not resolve to I.
Instead, it resolves to i, the parallel minor. At this point (bar 7) there is a dramatic textural change, triplet motion in the bass. Also, the bass has moved from slow movement in the higher register to rapid movement in the low register. So now every quality of the piece (tonality, rythym, and register) has been drastically changed.
The bass now arpeggiates for while, making chords easily definable by note name, but their implications become much more difficult to identify. The harmonic motion occurs each bar. Measure 8 is a clear D major arpeggio. If the piece were looked at purely linearly, one would be inclined to call this II .
But a II contains ‘F#’ and implies the presence of a ‘C#’ leading tone. There is obviously no room for these in a c minor key center. By looking beyond this bar, we see that everything after this point becomes related to ii. So the D major chord is really V7/iv/ii.
This moves appropriately to iv/ii in the next bar as a G minor arpeggio. The next bar is an A major arpeggio in the bass which is V/ii. So the past two bars have set up a iv-V progression which begs to resolve to i (ii in this case as it is really iv/ii-V/ii-i/ii). It does not resolve to ii.
There is a deceptive cadence to VI (a Bb arpeggio). The Bb is contiued in the next bar but the ‘g#’ in the melody gives the measure a very different tonality. The ‘Bb’ and ‘g#’ are on either sides of ‘A’. This chord is really a german 6th.
This a the german VI/ii, which usually resolves to V/ii and then ii. In this case it does go to V/ii in measure 13.There is a texture change in measure 13. The rythym that was in the bass is now in the treble and is not arpeggios but is a single repeated note figure with an octave jump the second triplet of each beat.
The figure in the bass is now eigth note motion with arpeggio implications at the end of each measure. The figure is an inversion of the idea in the treble throughout the past six bars. There is another dramatic change as well. The harmonic rythym has compressed to two harmonic events per measure as opposed to one.
This all contributes to more building of tension. The inverted figure, though, serves to provide some unity between this section and the last section. The second harmonic event in measure 13 is a ii chord, as promised by the german 6th (german VI/ii-V/ii-ii). The next measure is iv/ii a g minor chord, followed by an Edim.
The Edim tonicizes the F in the next measure, and is therefore viio/IV which moves to IV in the next measure. Here things get more ambiguous. In measure 15, the second harmonic event is unclear. The triplet figure in the treble uses ‘f’ and ‘a’.
The bass moves: ‘f’, ‘a’, ‘d’, and then ‘b’ natural in the next measure. The first part of the measure is a clear VI (F). The ‘f’ and ‘a’ seem like an extension of this tonality. The ‘a’ and the ‘d’ considered together seem to reinforce the idea of ii (d) being tonicized throughout the earlier section and suggest that it is still the key center here.
The ‘b’ natural (which is part of the ‘f’, ‘a’, ‘d’ eighth note figure) implies that the previous motion has been a kind of arpeggiation of V, the dominant of i or I (which have both been absent for a while). This figure is deliberately obscure and creates more ambiguity to make what comes later more effective. Measure 16 is clearly V65 for two beats. We now expect a strong resolution back to I or i.
Instead the tonal movement is deceptive as the next chord is a C#dim. It is not a familiar deceptive cadence but a deceptive move from V to viio/ii, a chord that implies a cadence to a chord that implies a completely different cadence. The viio/ii does cadence to ii in the next measure. The second harmonic event of bar 17 is V7/i which resolves to i in bar 18.
This means that the viio/ii did not really tonicize ii but rather set up the familiar ii-V7-i cadence. The second harmonic event of bar 18 is an Adim which is viio/VII. This mirrors the viio/ii figure in bar 16. This time, however, the viio does not resolve as expected.
The next measure starts with a D65 chord. This is the beginning of a progression that sets up IV. The ‘D’ chord is V65/ii/IV. The ii/IV comes in the last beat of bar 19 with a g minor chord.
This is the first of a ii-V-I set up (ii/IV-V/IV-I/IV). The downbeat of bar 20 is V65/IV. However, it is too weak an inversion and occurs too quickly (one beat) to establish ‘F’ (IV) as a key center. While the treble flirts with ‘F’ as a key center with tertiary harmony movement, the bass jumps to IV/IV with a Bb, delaying our arrival at a true key center.
Bar 20 does succeed in decreasing the tension of most of the developement. The previous seven bars have mainted similar motion in the treble, this measure breaks away from that. There has also been 2-3 suspension between beats one and two of each bar until now. This added tremendously to the tension earlier and increases the release of the arrival at measure 20.
There is an implied tonicization in the last half of a beat of bar twenty; a ‘b’ natural in the bass. It functions the same way the ‘b’ natural in the pickups to the second theme did. However, with all the tension we’ve seen, this half a beat is hardly convincing of a strong tonicization of I. It is a weak tonicization though, and that is elaborated on in the next two bars.
There is a C in the bass mimicking the treble triplet figure earlier. Measure 21 begins with a I (C) chord. The third beat is a viio which returns to I in bar 22. The third beat of bar 22 is an Italian 6th which moves back to I in bar 23 (the resolution in the chord from tritone to 6th is delayed one beat in the treble with a pedal C in the bass).
Tonal analysis is not the only important thing in these two bars. The figure that moves from 6-5 and 4-3 in the first beat of measure 21 is repeated with variation in the first beats of 22 and 23. The variations borrow from the parallel minor scales. This contributes to the ambiguity of C as I.
The tonic is still not clearly established. The fact that the bass moved from V to I from 20 to 21 but that VI was sustained in the treble implies that IV is not really gone. These things make the tonality vague, it’s the Italian 6th that defines the tonality. An Italian 6th is supposed to resolve to V and then to I.
Since the Italian 6th here resolves to C, then C must be V, which means what we thought was IV is actually I (F). This is why when the tritone in beat one of bar 23 resolves to C, we are not completely satisfied. When theme one returns in F the entire developement has been resolved.
The first theme reenters in its original key and the piece continues without much dilineation from the original exposition.
The first theme’s antecedant and consequent phrases occur twice, the second time with variation. The bridge, however, is quite different. The first bar of the bridge has similar rythymic and directional figures as the the begginning of the bridge in the exposition. The tonality, though, has changed.
Also the ambitus of the treble figures in the two first bars is opposite.
The bridge continues with a sequence of similar rythymic and directional figures, but the tonality sounds like modulation. While there is no real modulation to another solid key, there are secondary dominants. The bridges of the exposition are the same length (six measures) but the only nearly identical figure is in the last measure of the bridge: the I-V movement from beat one to beat two, and the implied tonicization of C using a ‘b’ natural in the pickups to the second theme.
There is a major difference this time, though. The ‘b’ natural is quickly negated by a ‘Bb’ in the continuing pickups. This sets up the second theme to be in F rather than C.
So the second theme occurs transposed to F but without much other deviance from the exposition.
The second theme, however, is followed by something very unusual; a five measure developement and variation of the second theme similar to the three measure rounding off in the exposition but unique enough that it cannot be called a simple rounding off. The closing material then enters with little variation other than the transposition to F. The two scale figures (formerly d melodic minor and G major in the exposition, g melodic minor and C major here) end on a viio on beat one and are followed by a weak V65 on beats two and three, which prepare for the final cadence. But since the dominant chord is weak, the ending is not fully prepared and there is another two measure codetta to round off to the final cadence: a strong V7-I with a pedal F that moves down an octave at the resolution of the upper staff.