Harpsichord with short, broken bass octave and
divided sharps for E-flat/D-sharp and G-sharp/A-flat, following early 17th century models

Already at the end of the 16th century, and then increasingly at the beginning of the 17th century, especially in Italy, sharps intended for different semitonas began to be divided, so that, for example, the G-sharp key was also available as an A-flat. This advantageously extended the use of the meantone tuning. The division of the G-sharp/A-flat and E-flat/D-sharp upper keys alone brought an enormous advantage in terms of freer use in the context of meantone tuning.