Just spotted this on the 3Leaf site. Closer inspection reveals it’s the board for the Octabvre MkIII. It has a dry out jack, which suggests it’ll also have a separate sub out. The other jack is interesting and is labelled “up sw”. I wonder if that’s short for “switch” or “sweep”. Perhaps expression control of the octave up? I know it’ll have octave up from something Spencer said on his Facebook page. Or perhaps it stands for “up/square wave” meaning it’s simply the output of the combined octave up and octave down signals.