3.3 Unfolding: a summary

Let's recap. An unfolding occurs when two structural voices, which belong together as part of the same harmony, are separated out through time, and are presented as a single melodic part. Both voices must behave according to the rules of good counterpoint (for instance, the seventh of a chord must fall downwards by step and a leading note will nearly always rise). For this reason, you should be careful not to identify unfoldings where the parts are dissonant with one another (for instance, the leaping downward intervals in Example 19 are not unfolded sevenths, which would produce a dissonant and ungrammatical effect). In terms of notation, as you have seen, the outer and inner voices are usually shown with stems pointing in different directions to signify that they belong to different strands of counterpoint. The notes of each unfolded interval may be connected by slurs (as in Example 19), or the stems may be connected by diagonal beams (as has been seen in the video analyses) – the latter are used especially when there are several notes in between the notes of the unfolded interval. Unfoldings are especially common in Mozart's music (indeed, it is rare to find a passage which does not feature them in some guise or other) and they are one reason for the richness of his melodic language.