Abstract: An organ stop switching system includes a plurality of stop switches and a random access memory within which combinations of stop switch settings are stored. The stop switch settings are multiplexed into a memory loop having a capacity fractionally smaller than the random access memory. This loop is used for an input and an output circuit for the random access memory during time slots corresponding to numbered pistons selected for storing and recalling stop setting combinations. A serial-to-parallel converter receives information from the memory loop and provides outputs for operating stop control circuitry of the organ.