Piano Concerto in A Major, K. 488, II. Adagio, m. 1-12

Roman Numeral Analysis – Piano Concerto in A Major, K. 488, II. Adagio m.-12
Key: F sharp minor
m. 1-4: i, iihalfdiminished42, V65, i, i64, ii(half)diminished6(5) (F sharp at beginning of second beat makes possibility of hearing half diminished), V64-53
m.5-7: VI6, viihalfdiminished7/III, IIIsharp2-3, i, IV65, V6
m.8-12: I4-3, VI, N6, V864-753, i

As the workbook states, the phrase structure of this excerpt is indeed difficult to analyze. First, the harmonies in m.5-6 function as tonic extension, but there is tonicization of III. The III does shift back to i in m. 6, strengthening the idea of III acting simply as tonic extension and adding harmonic interest in the phrase. Next, m. 5 – 8 feels like it could be a phrase as a whole, but the tonic extension at m. 8 from I4-3 to VI makes the end of m. 8 feel longing to continue and creates some harmonic ambiguity of establishing scale degree one since the V6 in m. 7 resolves to i m. 8, which then shifts to VI, another possible scale to resolve to from a dominant function chord, also in m. 8. Furthermore, VI’s ability to act as the fifth scale degree to flatII gives the feeling that the piece could continue in the key of flatII, which is what Mozart does by beginning m. 9 with the frequently occurring dottedeighth-sixteenth-eight note motif that begins the first phrase in m. 1 (it happens four times – m. 1, 5, 9, and 11, although m.11 is closing material as part of a cadential V864-753) which suggests the beginning of new phrases. However, Mozart does not continue the piece in flatII and uses N6 as a predominant to the cadential V864-753 in m. 11. Another issue is that, in contrast with the frequently recurring first motif of the piece, there is material from this passage only occurs once throughout this excerpt (sixteenth notes of m. 7, material in m 2-4).

One possible phrase diagram could be the following:
-It is a parallel period.
-m. 1-4 is one phrase, ending in a half cadence.
---Listeners may hear m. 1-2 as one subphrase, and the last beat of m.2-4 as a
second subphrase.
-m.5-12 is another phrase, ending in perfect authentic cadence.
---The first subphrase is m 5-7. The second subphrase is m. 7-8, and the last
subphrase is m. 9-12.

We can sum up the idea like this:

Phrase A - m. 1-4 Half Cadence
Subphrases:
a - m. 1-2
b - m. 2-4

Phrase A' - m. 5-12 Perfect Authentic Cadence
Subphrases:
a' - m. 5-6
c - m. 7-8
a’’ - m. 9-12

This beautiful passage requires much espressivo from the performer. Mozart does many inventive and unconventional things with the harmonic progressions and non-chordal embellishments for his time period, which calls for special attention to certain areas. Also, the beginning of this movement is a piano solo, which enables the pianist to give extra attention to portions of this excerpt without the troubles of staying together with the orchestra until the orchestra comes in at m. 12. The A natural of the second beat of m. 8 is a high point and a non-chordal accented embellishment, which could be stressed (but not accented!) in a caressing way. The traveling from I4-3 to VI then to N6 is quite a shock to listeners. The N6 of m. 9 is quite a color change and more distantly related to the tonic key than any of the other harmonic changes of the piece, so a change in tone and dynamics when one arrives at m. 9 – perhaps a soft, warm sound – would expose the beauty of the special N6 chord. The pianist could change the mood gradually to the warm, soft sound as the N6 is being approached from the harmonic changes of m. 8. On a final note, the proper release of tension in a sigh type of manner would be very musically satisfying. (For example, the release of sharp 2 to 3 in m. 6, the release of V64-53 of m. 4 and release of V864-753 of m. 11-12).