These are the two rows of figures which should be compared together for obtaining the inversions of double counterpoint at the twelfth:
Counterpoint | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 |
---|---|---|---|---|---|---|---|---|---|---|---|---|
Inversion | 12 | 11 | 10 | 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 |
It will be seen that the unison or octave changes, in counterpoint of this kind, into a twelfth, the second into an eleventh, etc.
The sixth, which by inversion becomes a seventh, should be prepared either in the upper part, or the lower; and the bass should then descend one note or degree.
Examples from Marpurg
This is an extended example of double counterpoint at the twelfth:
1st manner of inverting: Transpose the counterpoint a fourth below, while the theme remains in its place
2nd manner of inverting: Transpose the theme a twelfth below, while the counterpoint remains in its place
3rd manner of inverting: Transpose the theme an octave below, and the counterpoint a fifth below
4th manner of inverting: Transpose the theme a fifth above, and the counterpoint an octave below
This counterpoint is one of the most used, and one of the most fertile in resources.