Transcript

Robert Samuels

Now compare your graph with my analysis of these bars. Here's the score [graphic of score]. And now, we take out the rhythmic notation and the bar lines, and re-align the treble and bass slightly to make the consonances clear [graphic melts to analytical graph]. If we add the slurs to show the appoggiaturas in bar three, this is what you started with [add slurs].

Robert Samuels

and finally C [add stems]. Next, we show the B flat to A to B flat (plays) shape of the inner voice with downward stems [add stems]. Now we add stems to the main bass notes, which show a sort of contrary motion to the top voice, moving from B flat to C, D, and back to B flat (plays) before ending on the dominant, F [add stems]. The point where the melody moves via a passing note is in bar three (plays), where each note is also decorated by an appoggiatura. So we show this with a slur [add slur]. Now we use slurs to show the arpeggiation in bar one [plays & adds slurs], the subsidiary note and the harmonic interval in bar two [add slurs], and the way that the last appoggiatura in bar three is a neighbour note to the D [add slurs]. Finally, the notes in the bass form consonant skips [add slurs], this descending passing note feature [add slur], a larger-scale ascending passing note feature and a neighbour note to the final dominant harmony [add slur].

Now we are going to add three new notational symbols to make some middleground features even clearer. First of all, we are going to show which note in the top voice harmonises with which note of the structural alto voice in the three unfoldings. We do this by connecting together the stems with beams, which go diagonally like this [add diagonal beams]. Secondly, we indicate the voice exchange by straight lines crossing over to show the notes involved [add voice exchange lines]. Thirdly, the dominant chord at the imperfect cadence is emphasised in two ways which are also typical of the Classical style. It is ornamented by a 6/4–5/3 suspension, and it is has a prominent subsidiary harmony leading up to it over the E flat in the bass (plays). We show the suspension by using figures [add figures], and the subsidiary harmony, which we call a supporting harmony in this case, by adding a stem with a flag to the bass note.

Robert Samuels

This looks like a quaver, although it’s nothing to do with rhythm, but only with the function of the harmony [add flagged stem].

Now our graph is complete.

I hope that you feel you now understand how Mozart’s harmony works a little better. This is one of the main reasons for doing analysis, after all. But another thing that analysis can do is point out connections between different passages of music which we wouldn’t be able to describe otherwise. To show this at work, we are going to look at another four-bar extract from this Mozart sonata. But this isn’t from the same movement, but instead comes from the first movement. In fact, it’s the opening of the whole piece.

This is a very different melody in many ways from that of the last movement which we’ve just been analysing. It begins on an off-beat, it has very prominent appoggiaturas on the first crotchet of each bar, and it ends on the tonic rather than the dominant. But I want you to look now to see if you can identify any unfolded intervals in the melody.