Is the Anthony Gallo 3.5 speaker cable to be used only with the 3.5 without the SA?
I do not see a second OPT input for the second set of cable going to the Gallo SA.
OPT 2 involves the tweeter. The OPT wire connects to the inside of the tweeter core to suppress build up of static charge (the tweeter is a high voltage low current device). I would save your money and go with plain old wire and connect the OPT wire to the positive terminal.