A question regarding taking voltages the with a target of 0v but requiring a grounding of one test point while dialing in another. For the X11 EQ cards the instruction to "Test point 2 (TP-2) on the F-3451 EQ board must be temporarily connected to a ground point prior to taking voltage measurements at test point 1 (TP-1)." is a mystery to me. Wouldn't removing the temporary ground change the value measured at test point 1? I don't think the voltage would remain 0v after that temporary ground wire is removed. (To put it another way.) I know that the Sansui AU-907F Extra and the later G Extra both require a similar grounding of B before adjusting for A. Am I making a mistake here, and actually the grounding of B in order to adjust A really is not needed? I guess I am hoping for a visual example of this process begin done on some other models. I hope to better understand the process and goals of this requirement to ground B to adjust A.