We'll deal with Part B in our composition which according to our plan has to be in e minor. In this video, you will see the problems I got into when trying to connect Part A from video 1 with Part B.
The goal was to create a smooth bass line and avoid forbidden parallel octaves, fifths, augmented intervals, parallel motion of all voices, and accommodate the reach of wider intervals between the two hands since it's a piece for manuals only . It wasn't always easy, but the end was worth it.
Duo III (p. 3) by Antonio de Cabezón (1510-1566), a blind Spanish Renaissance composer and organist.