# Transcript

Robert Samuels
Well, how did you get on? I hope you noticed that the E natural in Bar One is a chromatic passing note. [play b. 1], which means that the harmony notes follow this line, in tenths with the bass [play D–E flat–F]. In bar two, there is a chromatic neighbour-note to the C natural [play C– B natural–C], and this C becomes an appoggiatura to the D natural [play C–C–D]. Then there's another appoggiatura, where the F natural is a neighbour-note to the E flat on the last beat: this E flat really harmonises the C natural in the bass under the F [play F–E flat then E flat]. This shows how the melody is working as a sequence based on the shape of three notes rising up a scale, and harmonised in tenths [play bb. 1–2, then bb. 1–2 reduction]. Now, in bar three, the B natural and C sharp are clearly chromatic passing notes [play b. 3].
And in bar four, the third beat is a 6/4 chord, which is nearly always a set of neighbour-notes to the following chord, making a cadence [play b. 4].
So if we write out just the harmony notes of the extract, we should have something like this. Look at the reduction on the screen while I play Mozart’s original.
You can see from this that Mozart continues the three rising notes of bars one and two in the melody of bars three and four.
We're going to use two more sorts of notation to analyse this sequence which is just below the surface of Mozart’s music. First, we can show the rising tenths in bars one and two.
Secondly, we are going to show how the same interval — a tenth — is approached in bars three to four. Here, the D in the top [highlight] and B flat in the bass [highlight] are approached from a B flat in the top [highlight] and a D in the bass [highlight]. This is a common way of writing a harmonic progression, and we call it “voice exchange”, because the top and bottom lines exchange their notes. We show it with two crossing lines to show where the exchange happens