As part of my Diabelli Project flash composition series, I wrote four sketches for a B-flat clarinet and bass clarinet duet. Even when I was sketching them out, I knew they were part of the same four movement work.
In Part 1 I posted the third movement, which is where I started with this piece. Here's the first movement.
Those seemingly random notes in the margins do have a purpose. I like to set a general metronome marking for the piece to begin with. I then calculate how many measures would encompass a minute at that tempo, how many for 30 seconds, and how many for 15 seconds. This helps me with the overall proportion of the movement.
In the upper right is the approximate playing time of each movement. Once again, this helps me keep the overall structure of the work in balance. (I'll be filling in the times for the second and fourth movements when they're completed.)
And just for comparison, here's the original Diabelli Project sketch this movement grew out of.