I found a PDF of the Low-rider (Pearl OC-7) which I built a long time ago. I no longer have the pedal but I was thinking of coming back to it.
I was looking at the schematic, and since I didn't find any use for the 2nd Octave down, I was wondering if the second Flip Flop chip (CD4013) is necessary even if we don't use the 2nd Octave down part of the schematic? Can I just omit it or is it serving some other purpose? I can see its CLK pin is connected the output pin on the other Flip Flop IC.
I have attached the schematic.
Yes, it looks like you could just eliminate it. IC4 is there only for the second octave. Disconnecting IC4 from IC3 would not cause a problem.
You could also remove the parts in the second octave part of the circuit, C18, IC5, etc.