So I feel that the CP-251 is a great component but I find myself needing another mixer. I have successfully breadboarded the MFOS Cv mixer. Recently I came across the the Moog modular mixer schematic, here is the link(page 55): http://www.hylander.com/images/schematics/moog/MoogModularServiceManual.pdf. I have a few questions before I breadboard this. I was curious why there are two 22 k resistors in series on the first feedback loop. Won’t this change the gain? Second, how does the negative offset pot work, is this similar to Doepfers bipolar offset mode? Also, does the CP 251 only have positive offset or unipolar offset? Third, are the resistors on the positive inputs pull down resistors? Finally are the diodes used the limit the voltage? Thanks.