Example 18. The percentage of the perfect sonorities on first breves of the modus unit compared to perfect sonorities on secondary breves in the IvTrem motets. The bar graphs are sorted according to the degree of difference between these two percentages. The graph on the left shows the imperfect modus motets; the graph on the right shows perfect modus motets. The motets to the right of the dotted line have less than a 10% difference between perfect sonorities at modus onset and on secondary breves