You convinced me to try and get an iteration in, just under the wire!
The process used is detailed in the SC description, but x-posting here for ease of consumption:
A small loop from the op-1 was sampled into the octatrack. The crossfader on the octatrack was used to jog around the loop (while also adjusting pitch, filter cutoff, and playback rate). The loop was triggered in real time using an egg shaker resting on top of the octatrack’s trigger. A room mic was set up to capture the egg shaker as well as ambient room noise to allow for additional character in each take. There are four layers.
Not sure if recording the initial loop counts as cheating, but I manually triggered it each time, and never allowed more than a note or two to play back before retriggering, so hopefully not! It kind of acted akin to a clumsy fretless bass.
This was super fun, look forward to participating in future juntos in the future. Thanks @tehn and @disquiet!