A-180-1 and A-180-2 are simple multi-connectors. They have eight inter-connected sockets, so that you can "multiply" any audio or control signal. From the factory the modules come as two four-fold multiples. But they can be modified as an eight-fold multiple (solder bridge on the pcb). Though these modules are very "primitive" they are required very often in patches (e.g. to distribute a clock signal or a control voltage). Within a big A-100 system sufficient multiples should be planned. The function of A-180-1 and A-180-2 is the same. The modules differ only in the front panel width.
For the distribution of control voltages used for pitch control of several VCOs the buffered multiple A-185-2 is recommended. This module has a built in buffer (and a lot of additional features like CV summing) that avoids small voltage losses that may be heard in pitch control applications.