With several 556 it sounds really noisy, and quite far from the sound of the basic APC, but it may be what you want
to compare my 1st APC + LFO (3x 555 in all)
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What is the difference between the red and white controls? And is that a photoresistor on the side?
there is 2 pot pitch (in serie, for a “fine pot”) and 2 pot modulation also
1 LFO rate pot and LFO mix pot
yes it’s an LDR on the side 
with a switch to open or not the LDR
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I added a Vactrol to test some sort of CV in, seems to work but having plugged in seems to offset the tone, if that makes sense. I’m not sure if it would be easier to have a socket plugged into the board but I’m not sure where it would go and if it would need resistors etc.
Here is a test with a Volca controlling the APC via a Vactrol:
